"He was a 23-year-old South Korean here in the US as a resident alien," Flinchum said at a press conference held at Blacksburg, Virginia where the university is located.

Cho was an undergraduate student in his senior year majoring in English, Flinchum said. He lived on campus at Harper Hall and his residence was established in Centreville, Virginia outside Washington.

Meanwhile, Colonel Steve Flaherty, Superintendent of Virginia State Police, said the same gun was used in the two shootings at the university, suggesting there was only one gunman.

Previous reports had said there was a possible second gunman still at large.

A total of two attacks took place at Virginia Tech Monday. The first attack happened at a dormitory around 7:15 a.m. and left two people dead, while the second attack took place at the campus two hours later.

A total of 33 people, including the gunman, were killed in the worst campus shooting rampage in US history.

Virginian Tech President Charles Steger said earlier Tuesday that all classes for the rest of the week had been cancelled.

A memorial service will be held at the campus Tuesday afternoon and US President George W. Bush will attend.

Before today, the deadliest campus shooting in the country took place in 1966 at the University of Texas in Austin, in which 17 people, including the gunman, were killed.

Founded in 1872, the state university has more than 25,000 full-time students. The school is best known for its engineering school and its powerhouse football team.