Officials in Blacksburg said Cho was registered in his senior year at Virginia Tech, majoring in English and living on campus. According to CNN, Harry Hincker, associate vice president for university relations, described Cho as a loner.

Cho had lived with his family in Centerville, Virginia, a suburb near Washington. He also had a room in one of the dormitories on the university campus, Harper Hall.

Cho was discovered on Monday among the dead at the scene of the second shooting at Virginia Tech. Col. Steve Flaherty, superintendent of Virginia State Police, said it was “a reasonable assumption” that Cho was responsible for both shootings at Virginia Tech.

Colonel Flaherty said Cho was “discovered among several of the victims in one of the classrooms. He had taken his own life.” He said that the evidence “has not led us to where we can say with all certainty that the same shooter was involved in both instances, so we are now exploring that evidence and trying to make that trail.”

“We also have no evidence to indicate that there was any accomplice at either event, but we are exploring whether or not there was someone who may or may not have helped Cho at any point during his planning or during his execution of this particular event,” he added.

(President George W Bush and first lady Laura Bush were to attend a memorial service at Virginia Tech later on Tuesday, Reuters reported. Television images of terrified students and police dragging out bloody victims revived memories of the Columbine High School massacre in 1999 and were likely to renew heated debate about America’s gun laws.)

In Centerville, Cho’s family lived in a small, two-level townhouse in an upper-middle-class development. Coincidentally, one of the victims lived less than a mile from the Cho family home.

The yellow aluminium-sided home was shuttered and police said they had removed the family from their home last night.

Outside the home, a local postman, Rod Wells, said that the family was “very quiet, very polite. They always had a smile on their face. I know they are a nice family. They have been very good to me.”

Cho was a 2003 graduate of Westfield High School in Clifton, Virginia. Officials of the Fairfax County Public Schools said other graduates from its schools might have been among those killed or injured in Monday’s shooting.

“He was very quiet, always by himself,” Abdul Shash, a neighbour, said of Cho, according to The Associated Press.

Shash said Cho spent a lot of his free time playing basketball, and wouldn’t respond if someone greeted him. He described the family as quiet.

Marshall Main, who lives across the street, told AP that the family had lived in the townhouse for several years.

Earlier this morning, a single spent long-rifle shell was discovered on the sidewalk near the entrance to the house. After the discovery, by news cameramen, police immediately moved reporters back and took the round away for investigation.

According to court records, the Virginia Tech Police issued a speeding ticket to Cho on April 7 for going 44 mph in a 25 mph zone, and he had a court date set for May 23, AP said.

CBS News reported that paperwork found in the gunman’s backpack allowed authorities to trace one of the two handguns used in the shootings, though the serial numbers for both weapons had been removed.

Virginia Tech is quite well-known in South Korea. South Korea’s Foreign Ministry expressed its condolences, and said South Korea hoped that the tragedy would not “stir up racial prejudice or confrontation.”

“We are in shock beyond description,” said Cho Byung-se, a ministry official handling North American affairs. “We convey deep condolences to victims, families and the American people.”

Thousands of South Korean students go to the United States annually to get American college diplomas. Diplomas from Ivy League universities and other well-known American schools, as well as English proficiency, are coveted in the South Korean job market.