Damascus: At least 50 civilians are being treated after a suspected poison gas attack by Syrian rebel groups on the government-held Aleppo city in the country's north, according to Syrian state media.

The number of people reportedly affected continues to rise - Syrian state TV earlier said that 21 people had been injured on Saturday, but people continued to arrive at a hospital in Aleppo where state TV was airing live.

Doctors told state TV that most of those admitted to hospitals suffered from breathing problems and blurred vision. One doctor said two were in critical condition, including a child. State TV showed footage of medical professionals treating men and women on hospital beds.

Rami Abdurrahman, the head of Britain-based Syrian Observatory for Human Rights, said there was a stench of gas in Aleppo city after projectiles were fired. </s> Damascus: At least 50 civilians are being treated after a suspected poison gas attack by Syrian rebel groups on the government-held Aleppo city in the country's north, according to Syrian state media.

The number of people reportedly affected continues to rise - Syrian state TV earlier said that 21 people had been injured on Saturday, but people continued to arrive at a hospital in Aleppo where state TV was airing live.

Doctors told state TV that most of those admitted to hospitals suffered from breathing problems and blurred vision. One doctor said two were in critical condition, including a child. State TV showed footage of medical professionals treating men and women on hospital beds.

Syrian rebels dismissed the government accusations they used poison gas. </s> DAMASCUS, Syria (AP) — The Latest on the Syrian conflict (all times local):

Syrian rebels have dismissed government accusations they used poison gas to attack government-held Aleppo city.

Rebel commander Abdel-Salam Abdel-Razak says the opposition doesn't possess poisonous gases or the capabilities to lob them. Abdel-Razak served in Syria's chemical weapons program before defecting to join the opposition in the early years of the conflict, which began in 2011.

Abdel-Razak tweeted that "These are lies" soon after reports emerged of an attack in Aleppo that injured dozens of people.

Rebel spokesman Mustafa Sejari dismisses the poison-gas claims. He says they came after government shells landed in rebel-held areas, violating a Russian-backed cease-fire. He says the government is trying to undermine the cease-fire.

A Syrian official says that at least 50 civilians were being treated Saturday following a suspected poison gas attack by Syrian rebel groups on the government-held Aleppo city in the country's north.

Syrian state TV previously said that 21 people had been injured, but people continued to arrive at a hospital in Aleppo where state TV was airing live.

Health official Haj Taha says at least 50 civilians have been injured.

Head of Britain-based Syrian Observatory for Human Rights Rami Abdurrahman said there was a stench of gas in Aleppo city after projectiles were fired.

Syrian state media is reporting that 21 civilians have been treated for breathing problems following a rebel attack it said involved projectiles filled with poisonous gas on the government-held city of Aleppo.

Syrian state TV aired footage late Saturday of the injured lying in hospital beds as doctors administered oxygen and other treatments.

State news agency SANA quoted a police officer in Aleppo saying the attack hit al-Khalidiya neighborhood. Syrian state TV later said the attack has also hit two other areas in the city and said a total of 21 people had been injured. State TV interviewed doctors in a hospital who said most people were suffering from breathing problems and blurred vision.

In the past, rebels have accused the government of using chlorine gas to attack opposition-held areas.

A joint team from the United Nations and the Organization for the Prohibition of Chemical Weapons accused Syria's government of using chlorine gas in at least two attacks in 2014 and 2015, and using the nerve agent sarin in an attack in April 2017 in the town of Khan Sheikhoun that killed about 100 people.

The UN-OPCW team also accused the Islamic State extremist group of using mustard gas twice in 2015 and 2016. </s> At least 50 civilians are being treated after a suspected poison gas attack by Syrian rebel groups on the government-held Aleppo city in the country's north, according to reports in Syrian state media.

Most of those admitted to hospitals had breathing problems and blurred vision, doctors told state TV. One doctor said on Saturday two were in critical condition, including a child. State TV showed footage of medical professionals treating men and women on hospital beds.

There was a stench of gas in Aleppo city after projectiles were fired, said Rami Abdurrahman, the head of Britain-based Syrian Observatory for Human Rights.

Rebel commanders and opposition figures discredited the government reports, denying they lobbed gas into Aleppo and accusing Damascus of seeking to undermine an existing cease-fire and efforts to kickstart political talks. Earlier on Saturday, government shelling of a rebel-held area in neighbouring Idlib province killed at least seven civilians.

In Aleppo city, local governor Hussein Diab visited the injured at the hospital. He told state TV that 41 people had been admitted and accused rebels of using poisonous gas in the missiles they lobbed at the Aleppo neighbourhood.

Health official Haj Taha later said the number of injured was up to 50, adding that symptoms suggest the gas used was chlorine. Further tests are needed, he said.

A cease-fire in Aleppo and Idlib has been fraying in recent days. Aleppo has come under rebel attack in recent weeks, with missiles falling inside the city. The government has responded with counter attacks on rebel-held areas in the Aleppo countryside. </s> DAMASCUS, Syria — The Latest on the Syrian conflict (all times local):

Syrian state media is reporting that 21 civilians have been treated for breathing problems following a rebel attack it said involved projectiles filled with poisonous gas on the government-held city of Aleppo.

Syrian state TV aired footage late Saturday of the injured lying in hospital beds as doctors administered oxygen and other treatments.

State news agency SANA quoted a police officer in Aleppo saying the attack hit al-Khalidiya neighbourhood. Syrian state TV later said the attack has also hit two other areas in the city and said a total of 21 people had been injured. State TV interviewed doctors in a hospital who said most people were suffering from breathing problems and blurred vision.

In the past, rebels have accused the government of using chlorine gas to attack opposition-held areas.

A joint team from the United Nations and the Organization for the Prohibition of Chemical Weapons accused Syria’s government of using chlorine gas in at least two attacks in 2014 and 2015, and using the nerve agent sarin in an attack in April 2017 in the town of Khan Sheikhoun that killed about 100 people.

The UN-OPCW team also accused the Islamic State extremist group of using mustard gas twice in 2015 and 2016. </s> At least 50 civilians were being treated Saturday following a suspected poison gas attack by Syrian rebel groups on the government-held Aleppo city in the country’s north, according to reports in Syrian state media.

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Most of those admitted to hospitals had breathing problems and blurred vision, doctors told state TV. One doctor said two were in critical condition, including a child. State TV showed footage of medical professionals treating men and women on hospital beds.

There was a stench of gas in Aleppo city after projectiles were fired, said Rami Abdurrahman, the head of Britain-based Syrian Observatory for Human Rights.

Rebel commanders and opposition figures discredited the government reports, denying they lobbed gas into Aleppo and accusing Damascus of seeking to undermine an existing cease-fire and efforts to kickstart political talks. Earlier Saturday, government shelling of a rebel-held area in neighbouring Idlib province killed at least nine civilians.

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In Aleppo city, local governor Hussein Diab visited the injured at the hospital. He told state TV that 41 people had been admitted and accused rebels of using poisonous gas in the missiles they lobbed at the Aleppo neighborhood.

Health official Haj Taha later said the number of injured was up to 50, adding that symptoms suggest the gas used was chlorine. Further tests are needed, he said.

The projectiles landed in the al-Khalidiya neighbourhood, and wind caused gas to spread, Aleppo police chief Essam al-Shali told state TV. State TV later said the gas affected two other areas in the city. There are no deaths, al-Shali said.

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One patient said a foul smell filled the air after projectiles were lobbed.

“There are often missiles on the city but this is the first time we smelled such a smell,” the patient said without giving his name.

State TV later said government troops retaliated, hitting the source of the attack. It didn’t elaborate.

A cease-fire in Aleppo and Idlib has been fraying in recent days. Aleppo has come under rebel attack in recent weeks, with missiles falling inside the city. The government has responded with counter attacks on rebel-held areas in the Aleppo countryside.

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Earlier Saturday, rescue works and the Britain-based Syrian Observatory for Human Rights said government shells landed in Jarjanaz, a rebel-held town in Idlib province, hitting students as they were leaving their school. The shelling killed eight, including six children, according to the civil defense team in the opposition-held area.

The opposition fighters don’t have chemical weapons or the means to lab them, rebel commander Abdel-Salam Abdel-Razek said. On Twitter, he accused the government of staging the attack to frame the rebels.

Rebel spokesman Musafa Sejari said the government is seeking to undermine the cease-fire deal.

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In the absence of independent monitors, it is difficult to corroborate gas attacks. But both sides of the conflict have accused each other throughout the war of using poison gas.

A joint team from the United Nations and the Organization for the Prohibition of Chemical Weapons accused Syria’s government of using chlorine gas in at least two attacks in 2014 and 2015, and the nerve agent sarin in an attack in April 2017 in the town of Khan Sheikhoun that killed about 100 people. The U.S. launched a series of strikes on Syrian government sites in retaliation for the attack in Khan Sheikhoun.

The UN-OPCW team also accused the Islamic State extremist group of using mustard gas twice in 2015 and 2016.

The government accused rebels of using gas in a 2013 attack on Khan al-Assal, a village southwest of Aleppo city, that killed 25 people. </s> At least 58 are dead after a suspected chemical attack in the northern Syrian town of Khan Shaykhun, the Associated Press reports. Local activists described the attack as the worst since the 2013 toxic gas attack in Ghouta, a suburb of Damascus, which killed hundreds.

The number of dead comes from the Syrian Observatory for Human Rights, which also said that 11 of the 58 dead were children. Activists believe the airstrike was carried out either by the Syrian government or Russian warplanes, according to the AP,

The White Helmets, a volunteer civil defense organization, posted pictures to their Twitter account of people being rushed to hospitals for treatment after the attack.

The suspected chemical attack is the third in Syria in just over a week. Both previous attacks occurred in the Hama province, not far from Khay Shaykhun, according to the AP.

The Syrian American Medical Society, a nonprofit medical relief organization, said it sent inspectors to Khan Shaykhun and that an investigation is underway. Currently, the group has no information on the chemical agent used in the attack.

After the 2013 attack, president Bashar Assad agreed to destroy his 1,300-ton stockpile of chemical weapons and "precursor chemicals" used to make weapons. Though they were destroyed, chlorine was not part of the chemical weapons agreement. Activists say they have seen dozens of chlorine gas attacks since then. According to the AP, the Syrian government has repeatedly denied using chlorine gas for attacks, accusing rebels of using it, instead.

However, doctors suspect it may be more than one kind of gas, as chlorine gas does not cause convulsions, which is a major symptom of Tuesday's gas attack. They suspect sarin may be one of the other gases.

A media activist told the AP that the local hospital is equipped to handle chemical attacks because of previous instances of chemical warfare.

The wounded have been "distributed around in rural Idlib," Mohammed Hassoun told the AP. "There are 18 critical cases here. They were unconscious, they had seizures and when oxygen was administered, they bled from the nose and mouth."

One Syrian man who lost his niece and her family in the attacks told the AP the attack happened early, as people were still in bed.

Idlib, Khan Shaykhun's procince, is controlled almost entirely by Syrian opposition and home to about 900,000 displaced Syrians, the AP reports. Because of its high concentration of displaced, opposition officials fear the government may be planning a concentrated attack on the area. </s> BEIRUT (Reuters) - A suspected chlorine gas attack on an opposition-held neighborhood in the Syrian city of Aleppo caused dozens of cases of suffocation on Tuesday, rescue workers and a monitoring group said.

The Syrian Civil Defense, a rescue workers’ organisation that operates in rebel-held areas, said government helicopters had dropped barrel bombs containing chlorine on the Sukari neighborhood in eastern Aleppo.

The Syrian government has denied previous accusations it used chemical weapons during the five-year-old civil war. The Syrian army could not be immediately reached for comment on the latest allegations.

The Civil Defense said on its social media page that 80 people had suffocated. It reported no deaths. It posted a video showing wheezing children doused in water using oxygen masks to breathe.

The British-based Syrian Observatory for Human Rights, which tracks Syrian violence using sources on the ground, said medical sources had reported 70 cases of suffocation.

A United Nations and Organization for the Prohibition of Chemical Weapons inquiry seen by Reuters last month found that Syrian government forces were responsible for two toxic gas attacks in 2014 and 2015 involving chlorine.

The Civil Defense accused the government of two other suspected chlorine gas attacks in August . The United Nations Commission of Inquiry on Syria said it was investigating an August incident.

“Unimaginable crimes are occurring in Aleppo … pro-government aerial bombardments cause mass civilian casualties,” Commission Chairman Paulo Pinheiro told reporters in Geneva. “In government-held areas, indiscriminate ground shelling (by) armed groups … is also killing scores of civilians,” he added.

Aleppo has been one of the areas hardest hit by escalating violence in recent months after the collapse of a partial truce brokered by the United States and Russia in February.

Government forces put eastern Aleppo under siege on Sunday for a second time since July after advancing against terrorists on the city’s outskirts. The city has long been divided between government and opposition areas of control.

The Syrian conflict has killed more than 250,000 people and forced more than 11 million from their homes. </s> In this photo released by the Syrian official news agency SANA, shows a woman receiving oxygen through respirators following a suspected chemical attack on her town of al-Khalidiya, in Aleppo, Syria, Saturday, Nov. 24, 2018. Some 50 civilians were being treated following a suspected poison gas attack by Syrian rebel groups on the government-held Aleppo city in the country's north, according to Syrian state media. (SANA via AP)
Syrian state media report that more than 50 civilians are injured in a suspected poison gas attack by Syrian rebels on Aleppo.