April 17, 2007 Cho Seung-Hui, the student who killed 32 people and then himself yesterday, left a long and "disturbing" note in his dorm room at Virginia Tech, say law enforcement sources.

Sources have now described the note, which runs several pages, as beginning in the present tense and then shifting to the past tense. It contains rhetoric explaining Cho's actions and says, "You caused me to do this," the sources told ABC News.

Sources say Cho, 23, killed two people in a dorm room, returned to his own dorm room where he re-armed and left the note, then went to a classroom building on the other side of campus. There, he killed 30 more people in four classrooms before shooting himself in the head.

Cho, born in South Korea, was a legal resident alien of the United States. He was a senior at Virginia Tech, majoring in English.

Sources tell ABC News Cho bought his first gun, a Glock 9 millimeter handgun, on March 13; they say he bought his second weapon, a .22 caliber pistol, within the last week. The serial numbers on both guns had been filed off, they said.

Authorities found the receipt for the 9 millimeter handgun in Cho's backpack. They say the bag also contained two knives and additional ammunition for the two guns.

Legal permanent resident aliens may purchase firearms in the state of Virginia. A resident alien must, however, provide additional identification to prove he or she is a resident of the state.

Sections of chain similar to those used to lock the main doors at Norris Hall, the site of the second shooting that left 31 dead, were also found inside a Virginia Tech dormitory, sources confirmed to ABC News.

Positive Fingerprint Match

Cho's identity has been confirmed by matching fingerprints on the guns used in the rampage with his immigration records.

"Lab results confirm that one of the two weapons seized in Norris Hall was used in both shootings," Virginia Tech Police Chief Wendell Flinchum said at a press conference Tuesday morning.

At this time, police are not looking for a second shooter, though they did not rule out the possibility that Cho could have had an accomplice.

Cho, according to law enforcement officials, had entered the country through Detroit with his family in 1992, at the age of eight. He last renewed his green card in 2003. As of yesterday, his home address was listed as Centreville, Va., and the university reported he was living in a campus dormitory, Harper Hall.

Cho's parents live in a townhouse development in Centreville, a suburb of Washington. They own a dry-cleaning shop nearby. Police searched their home last night. On Tuesday, no one was answering their door.

One neighbor, Marshall Main, describes Cho's parents as quiet and polite. Neither Main nor another neighbor recalled seeing the son in recent years.

Cho graduated from Westfield High School, a Fairfax County public school, in 2003. The school system says two of the dead yesterday at Virginia Tech had graduated from Westfield in 2006; they would have been freshmen when Cho was a senior.

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