Monday's deadly gun rampage assailant at the Virginia Tech University was a South Korean immigrant who had been in the United States since 1992 and who held a green card signifying his status as a legal permanent U.S. resident.
Cho Seung-Hui, a 23-year-old English major, was listed with a home address in a suburb of Washington.
Immigration records maintained by the Department of Homeland Security show that Cho was born in South Korea on Jan. 18, 1984 and entered the United States through Detroit on Sept. 2, 1992. He had last renewed his green card on Oct. 27, 2003.
University officials said he lived in a dormitory on the Virginia Tech campus, but could shed no light on a motive for the shooting spree that left 33 dead. "He was a loner, and we're having difficulty finding information about him," said Virginia Tech spokesman Larry Hincker.
Cho's fingerprints were found on two handguns used in the rampage, said two law enforcement officials who spoke on condition of anonymity because the information had not been announced. The serial numbers on the two weapons had been filed off, the officials said.
Ballistics tests by the federal Bureau of Alcohol, Tobacco and Firearms showed that one of the guns was used in both of Monday's separate campus attacks that happened two hours apart.
Cho was found with a backpack containing a receipt for a Glock 9mm pistol that he had bought in March.
As a permanent legal resident of the United States, Cho was eligible to buy a handgun unless he had been convicted of any felony criminal charges, a federal immigration official said.
The South Korean Embassy has sent three officials to Virginia. The ambassador, Lee Tae-sik, was out of Washington but was returning to the embassy. In a statement, the embassy said it was "shocked and dismayed by the violent crime."
"We express our deep sympathy and most sincere condolences to the victims and their families and friends."