A student was stabbed to death by his roommate during a quarrel in Nanhang Jincheng College in Nanjing, Jiangsu province, on Tuesday night, the school and police confirmed.

The 22-year-old student surnamed Jiang, who forgot to bring his key, knocked on the door of the dormitory and asked his roommate, surnamed Yuan, to open the door for him, according to the Jiangning district police. But when Yuan opened the door several minutes later the two students had a fierce argument before Yuan grabbed a fruit knife from a bookcase and stabbed Jiang in the chest, police said.

"Yuan didn't open the door in the first place because he was playing an online computer game," said Wang, a 19-year-old student from the college who asked to be identified only by his last name.