Question: Ivan Cooper led an anti-internment march which developed into a massacre where how many people died ?

Context paragraphs:
Effects of Hurricane Floyd in Pennsylvania: The effects of Hurricane Floyd in Pennsylvania were concentrated in southeastern portions of the state, and included over a dozen deaths.  Hurricane Floyd made landfall in North Carolina and, in a weakened state, impacted the Mid-Atlantic States with torrential rainfall.  Over 10 in of rain in the state caused extensive and damaging flash flooding that affected over 10,000 homes.  Many people became stranded due to the flood waters, and thousands had to be evacuated.  Relatively strong winds resulted in widespread downed trees, some of which landed on houses and vehicles.  Total preliminary damage from the storm was $60 million, and it is estimated that 13 people died due to the storm.  Following the floods, multiple counties were declared major disaster areas.

Ivan Cooper (cricketer): Ivan Cooper (28 January 1896 – 2 August 1968) was a New Zealand cricketer.  He played thirteen first-class matches for Auckland between 1924 and 1927.

Bloody Sunday (1972): Bloody Sunday – sometimes called the Bogside Massacre – was an incident on 30 January 1972 in the Bogside area of Derry, Northern Ireland, when British soldiers shot 28 unarmed civilians during a peaceful protest march against internment.  Fourteen people died: thirteen were killed outright, while the death of another man four months later was attributed to his injuries.  Many of the victims were shot while fleeing from the soldiers and some were shot while trying to help the wounded.  Other protesters were injured by rubber bullets or batons, and two were run down by army vehicles.  The march had been organised by the Northern Ireland Civil Rights Association (NICRA).  The soldiers involved were members of the 1st Battalion, Parachute Regiment, also known as "1 Para".

Great Fire of Northampton: The Great Fire of Northampton occurred in September 1675 in Northampton in Northamptonshire, England.  The blaze was caused by sparks from an open fire in St. Mary’s Street, near Northampton Castle.  The fire devastated the town centre, destroying about 700 buildings [out of 850] including All Saints church, in six hours.  Three quarters of the town was destroyed, 11 people died and about 700 families were made homeless.  Many people escaped the fire by going through Welsh House on the market square to safety.

Helmet massacre: The Helmet massacre (Portuguese: "massacre do Capacete" ] ) of the Tikuna people took place in March 1988, in the municipality of Benjamin Constant, in the Alto Solimões region, in a remote area in the state of Amazonas.  Funai, the National Foundation for the Indians, had begun to demarcate the Tikuna land, giving rise to reactions from local squatters.  The indigenous people were gathered in an assembly and were unarmed when they were attacked.  During the massacre four people died, nineteen were wounded, and ten disappeared in the Solimões river.  It was initially treated as homicide.  Since 1994 it has been treated by the Brazilian courts as a genocide.  Thirteen men were convicted of genocide in 2001.  In November 2004 at the appeal before Brazil's federal court, Castelo Branco, the man initially found guilty of hiring men to carry out the genocide was acquitted, and the other men had their initial sentences of 15–25 years reduced to 12 years.

Mayakovsky (ship): On August 13, 1950 the steamer Mayakovsky (named for Soviet poet Vladimir Mayakovsky) sank at around 12:00 pm local time due to overloading the vessel with too many people.  "Mayakovsky" sank in the center of Riga, just 12 to 15 meters (38 to 49 feet) from the present day site of the Stone Bridge.  A total of 147 people died, including 48 children.  It was the deadliest peacetime disaster in Soviet Latvian history.

August 1950: On August 13, 1950 the steamer Mayakovsky (named for Soviet poet Vladimir Mayakovsky) sank at around 12:00pm local time due overloading the vessel with too many people.  Mayakovsky sank in the center of Riga, just 12–15 meters from the present day site of the Stone Bridge.  A total of 147 people died, including 48 children.  It was the deadliest peacetime disaster in Soviet Latvian history.

Casualties of the Iranian Revolution: Observers differ on how many people died during the Iranian Revolution.  The number of casualties suffered by protesters and revolutionaries at the hands of the Shah's regime during the revolution is either close to 60,000, or around 200, depending on whether the estimates used are those of Islamic government or from historians in Western countries.  The number of protesters and political prisoners killed by the new Islamic regime after the fall of the Shah is estimated by human rights groups to be several thousand.

Torca Island: Torca Island was an inhabited phantom island said to be located in the Indian Ocean, possibly in the East Indies.  It purportedly vanished when a volcano erupted on June 4, 1693.  The survivors escaped to a nearby island called Amboy (also called Amboyan, present-day Ambon Island) on 18 July 1693.  The villagers attempted to flee in canoes or by swimming, but many people died attempting to do this.

Ivan Cooper: Ivan Averill Cooper (born January 1944) is a former politician from Northern Ireland who was a member of the Parliament of Northern Ireland, and a founding member of the SDLP.  He is best known for leading an anti-internment march which developed into the Bloody Sunday massacre on 30 January 1972, in Derry, Northern Ireland.

Supporting paragraphs: Ivan Cooper Bloody Sunday (1972)
Answer: Fourteen people died