V州警方刚刚证实校园屠杀案凶手为二十三岁的来自南韩拥有美国居留绿卡的学生Cho Seung-Hui.Cho为该校英文系的学生.

South Korea was behind the massacre of at least 30 people locked inside a campus building in the deadliest shooting rampage in modern U.S. history, the university said Tuesday.

Ballistics tests also show that one of the guns inside that building was used in another shooting two hours earlier, at a dorm, Virginia State Police said.

Police identified the shooter as Cho Seung-Hui, 23, a senior from South Korea who was in the English department at Virginia Tech and lived on campus.

"It's certainly reasonable to assume that Cho was the shooter in both cases," but authorities haven't made the link for sure, said Col. Steve Flaherty, superintendent of the Virginia State Police.

A law enforcement official, speaking on condition of anonymity because the information had not been announced, said Cho was carrying a backpack that contained receipts for a March purchase of a Glock 9 mm pistol.