Question: When did the torch arrive in the city where Kim Il-sung University is located?

full_context: Document 1: Kim Jong-nam: Kim Jong-nam was born 10 May 1971 in Pyongyang, North Korea, to Song Hye-rim, one of three women known to have had children with Kim Jong-il. Because Kim Jong-il aimed to keep his affair with Song a secret due to the disapproval of his father Kim Il-sung, he initially kept Jong-nam out of school, instead sending him to live with Song's older sister Song Hye-rang, who tutored him at home. North Korea Leadership Watch says he left North Korea to visit his grandmother in Moscow, Soviet Union, and spent his childhood at international schools in both Russia and Switzerland until returning to his home country in 1988.
Document 2: Kim Il-chol: He was born in Pyongyang in 1933. He graduated from Mangyongdae Revolutionary School and the "Soviet Union Naval Academy". Although the North Korean army mainly depends on ground troops, Admiral Kim who was commander of the Korean People's Navy since 1982 was installed in the highest military position of the head of the Minister of the People's Armed Forces in 1998, filling a vacancy left by Choe Kwang, who died in February 1997, something that indicated that he was fully trusted by Kim Jong-il. Kim Il-chol participated as a senior delegate in the inter-Korean Defense Minister’s meeting held for the first time since the division of the Korean peninsula in September 2000.
Document 3: Hyon Chol-hae: During the Korean War, Hyon served as Kim Il-sung's bodyguard, a role which gave him "a place in North Korea's revolutionary history". He was director of the General Logistics Department of the Korean People's Army from 1986 to 1995, when he was appointed deputy director of the General Political Department, becoming one of the senior most members of the North Korean military and political leadership. He has been described as being in "close proximity" to Kim Jong-il, and as reporting directly to him. It had been suggested that, following Kim Jong-il's death, he may have taken part in a military council leadership of the country. He was transferred to director of the Standing Bureau of the National Defence Commission. He has been a member of the Central Committee of the Workers' Party of Korea since 1991.
Document 4: An Kyong-ho: He was born in Gangwon, and is a graduate of Kim Il-sung University in Pyongyang. He currently serves as the Chief Director of the Committee for the Peaceful Reunification of the Fatherland. He first entered international news in 1988, when he attended South-North preparatory talks. He was a delegate to the 9th and 11th sessions of the Supreme People's Assembly, held in 1990 and 2003.
Document 5: Paek Se-yun: Paek Se-yun, sometimes written Paek Se-yoon, is the president of North Korea's Korea Computer Company. He has served in that capacity since 2000. In the same year, he was awarded the Order of Kim Il-sung. Paek has also been an alternate member of the Central Committee of the Workers' Party of Korea since 1988. He was a delegate to the ninth Supreme People's Assembly, 1990-1998.
Document 6: 2008 Summer Olympics torch relay: North Korea: The event was held in Pyongyang on April 28. It was the first time that the Olympic torch has traveled to North Korea. A crowd of thousands waving pink paper flowers and small flags with the Beijing Olympics logo were organized by the authoritarian regime watched the beginning of the relay in Pyongyang, some waving Chinese flags. The event was presided over by the head of the country's parliament, Kim Yong Nam. The North, an ally of China, has been critical of disruptions to the torch relay elsewhere and has supported Beijing in its actions against protests in Tibet. Kim passed the torch to the first runner Pak Du Ik, who played on North Korea's 1966 World Cup soccer team, as he began the 19-kilometre route through Pyongyang. The relay began from the large sculpted flame of the obelisk of the Juche Tower, which commemorates the national ideology of Juche, or "self-reliance", created by the country's late founding President Kim Il Sung, father of leader Kim Jong Il, who did not attend.
Document 7: 2008 Summer Olympics torch relay: In many cities along the North American and European route, the torch relay was protested by advocates of Tibetan independence, animal rights, and legal online gambling, and people protesting against China's human rights record, resulting in confrontations at a few of the relay locations. These protests, which ranged from hundreds of people in San Francisco, to effectively none in Pyongyang, forced the path of the torch relay to be changed or shortened on a number of occasions. The torch was extinguished by Chinese security officials several times during the Paris leg for security reasons, and once in protest in Paris.
Document 8: 2008 Summer Olympics torch relay: Thailand: The April 18 relay through Bangkok was the Olympic flame's first visit to Thailand. The relay covered just over 10 km, and included Bangkok's Chinatown. The torch was carried past Democracy Monument, Chitralada Palace and a number of other city landmarks. M.R. Narisa Chakrabongse, Green World Foundation (GWF) chairwoman, withdrew from the torch-running ceremony, protesting against China's actions in Tibet. Several hundred protesters were present, along with Olympic supporters. Thai authorities threatened to arrest foreign protesters and ban them from future entry into Thailand. A coalition of Thai human rights groups announced that it would organise a "small demonstration" during the relay, and several hundred people did indeed take part in protests, facing Beijing supporters. Intended torchbearer Mom Rajawongse Narissara Chakrabongse boycotted the relay, to protest against China's actions in Tibet. In Bangkok, students told the media that the Chinese Embassy provided them with transportation and gave them shirts to wear.
Document 9: North Korea at the 2008 Summer Olympics: North Korea (Democratic People's Republic of Korea) competed in the 2008 Summer Olympics, held in Beijing, People's Republic of China from August 8 to August 24, 2008. The country sent 63 athletes, competing in 11 sports.
Document 10: Kang Sok-ju: Having obtained a Bachelor's degree in French from the University of International Affairs in Pyongyang, Kang began a diplomatic career. His first significant position was as the Korean Workers' Party's deputy director for international affairs, and then director.
Document 11: Kim Jong-un: Scarce information on Kim Jong - un's early life comes from North Korean defectors and people who have claimed to witness him abroad, such as during his school attendance in Switzerland. Some of the information has been conflicting and contradictory, perhaps confusing him with his brother, Kim Jong - chul, who also attended school in Switzerland around the same time. Nevertheless, there has been some consensus on information about his early life. North Korean authorities have stated that his birthdate is 8 January 1982, but South Korean intelligence officials believe the actual date is a year later. Former basketball star Dennis Rodman said that the birthdate is 8 January 1983 after meeting Kim in September 2013 in North Korea. Kim Jong - Un was the second of three children Ko Yong - hui bore to Kim Jong - il; his elder brother Kim Jong - chul was born in 1981, while his younger sister, Kim Yo - jong, is believed to have been born in 1987.
Document 12: 2008 Summer Olympics torch relay: Kazakhstan: The first torchbearer in Almaty, where the Olympic torch arrived for the first time ever on April 2, was the President of Kazakhstan Nursultan Nazarbaev. The route ran 20 km from Medeo stadium to Astana Square. There were reports that Uighur activists were arrested and some were deported back to China.
Document 13: U Tong-chuk: According to official North Korean state media, U graduated from Kim Il-sung University with a philosophy degree. He later served in a number of minor posts in the Organization and Guidance Department of the Workers' Party of Korea before being moved to a leading position in the Ministry of State Security (or State Security Department) in the 1990s. He was promoted to colonel-general, member of the National Defence Commission, and first vice-minister of State Security in 2009. This put him in charge of the ministry and gave him access to the country's top echelon, as the ministry was reportedly under Kim Jong-il directly, and he accompanied Kim Jong-il on a number of tours and official events, including a dinner with former US President Bill Clinton. On 28 September 2010, the 3rd Party Conference elevated him to member of the Politburo and the Central Military Commission; the day before he had been promoted to general of the Korean People's Army.
Document 14: 2018 Winter Olympics torch relay: The 2018 Winter Olympics torch relay began 24 October 2017 and ended on 9 February 2018, in advance of the 2018 Winter Olympics. After being lit in Olympia, Greece, the torch traveled to Athens on 31 October. The torch began its Korean journey on 1 November, visiting all Regions of Korea. The Korean leg began in Incheon: the torch travelled across the country for 101 days. 7,500 relay runners participated in the torch relay over a distance of 2,017 km. The torchbearers each carried the flame for 200 metres. The relay ended in Pyeongchang's Olympic Stadium, the main venue of the 2018 Olympics. The final torch was lit by figure skater Yuna Kim.
Document 15: 2008 Summer Olympics torch relay: After being lit at the birthplace of the Olympic Games in Olympia, Greece on March 24, the torch traveled to the Panathinaiko Stadium in Athens, and then to Beijing, arriving on March 31. From Beijing, the torch was following a route passing through six continents. The torch has visited cities along the Silk Road, symbolizing ancient links between China and the rest of the world. The relay also included an ascent with the flame to the top of Mount Everest on the border of Nepal and Tibet, China from the Chinese side, which was closed specially for the event.
ground_truth: April 28
sub_queries: Kim Il-sung University >> located in the administrative territorial entity Answer: Pyongyang
When did the torch arrive in Pyongyang ? Answer: April 28