Jan. 18, 1984: Cho Seung-Hui is born near Seoul, South Korea.
Sept. 1992: Family immigrates to United States and settles in Detroit, later moving to Centreville, Va., a suburb of Washington, where his parents run a dry cleaners.
Spring 2003: Cho graduates from Westfield High School. He was a member of the science club.
Oct. 2003: Renews green card but keeps Korean citizenship.
Fall 2005: At Virginia Tech, on the first day of a literature course, classmates say Cho refuses to introduce himself and puts a question mark on a sign-in sheet.
Oct. 2005: Odd behaviour surfaces in Cho's writing. His violent themes disturb poetry professor Nikki Giovanni. She confronts him about the dark glasses and cap he wears, but he refuses to remove them. Without asking, he snaps cellphone photos of classmates.
Giovanni complains students are scared of him and have stopped coming to class. At one point, she has guards stationed nearby. Giovanni tells department head Lucinda Roy she will resign unless Cho is removed.
Roy contacts police, who say his work doesn't contain direct threats. Roy advises Cho to seek counselling. He doesn't.
Oct. to Dec. 2005: Roy meets with Cho for three tutoring sessions.Nervous, she works out a code with her assistant in the event Cho becomes unstable. Roy gives him an A for the semester. Her colleagues believe it is because she was intimidated.
Nov. 27 2005: Cho makes "annoying" contacts with a co-ed by phone and in person. She complains to Virginia Tech police but doesn't press charges.
Dec. 13, 2005: Another female student complains of disturbing text messages from Cho. Police warn him to stay away from her. His parents tell police he may be suicidal and ask that he get counselling. After one session, Cho is voluntarily admitted to a behavioural health centre for one or two days. A doctor's report shows Cho was depressed, but his insight and judgment were normal and he denies suicidal tendencies.
Fall 2006: Cho's play Richard McBeef features a 13-year-old who accuses his stepfather of being a sexual deviant. Classmates are alarmed after the play is posted online for peer review. They fear he could be a school shooter. When reviewing his play in class, all choose their words carefully "in case he decided to snap," said ex-classmate Ian McFarlane in a blog yesterday. "Even the professor didn't pressure him to give closing comments."
Feb. 2007: Cho legally buys a .22-calibre Walther at a pawnshop in Blacksburg.
Feb. 2007: A candidate for student council visits suite Cho shares with five other students. Cho refuses to accept the candy offered to him.
March 12, 2007: Cho uses credit card to legally buy a 9-mm Glock 19 pistol and 50 rounds of ammunition from Roanoke Firearms costing $571. A background check is completed in about a minute.
April 2, 2007: An anonymous bomb threat is made to Torgersen Hall at Virginia Tech.
April 10, 2007: Cho begins to assemble the package he will send to NBC News in between shootings on April 16. Included are photos, videos and 1,800-word manifesto called "very angry, profanity-laced."
April 13, 2007: An anonymous bomb threat is made to three residence halls and engineering building. A written bomb threat similar to those phoned in was found in Cho's room after the shooting.
April 16, 2007:
5 a.m.: Roommate Joe Aust is awakened by Cho as he works on his computer.
5:30 a.m.: Roommate Karan Grewal bumps into Cho in the bathroom, where he brushes his teeth, wets his contact lenses and applies moisturizer. He's in boxer shorts and a T-shirt. As usual, Cho doesn't say a word.
Aust said Cho recently began getting up at about 5:30 a.m., popped prescription pills every day. Recently, he went to the campus gym at night to lift weights. He cut his hair into a military-style buzz.
Aust said Cho may have had an imaginary girlfriend, a supermodel named "Jelly."
7:15 a.m.: Virginia Tech police receive a 911 call about shots fired at West Ambler dormitory. Investigators discover the bodies of a male and female student. They believe it's a domestic dispute gone bad.
9:01 a.m.: Cho mails his package to NBC, received at a Virginia post office about an hour and 45 minutes after dorm shootings."He had the wrong address and ZIP code," said Steve Capus, NBC News president.
Police believe he also returned to his dorm to reload his guns.
9:15 a.m.: While interviewing a "person of interest" about the double murders, police are alerted to shots fired at Norris Hall engineering building.
9:45 a.m.: Police arrive to find the front doors chained from inside. As investigators ram open doors, shots are being fired on the second floor. Bodies are found scattered in four rooms and the stairwell. Cho has killed himself. A 9-mm Glock and new Walther P22 are found near his body. The serial numbers had been filed off. One was used in the earlier shootings.
Witnesses say he calmly shot point-blank at students and professors, firing through doors at others who tried to barricade themselves. He never wavered, often reloading. He shot many people three or more times at close range.
Police search Cho's bedroom and recover chain and combination lock. Also seized were a folding knife; two computers, a hard disk and floppy disks; documents, books, notebooks and writings; a digital camera; compact disks; and two Dremel tools used for cutting and sanding. The writings include rants about wealthy kids and debauchery.
April 18, 2007: Cho's manifesto arrives at NBC.
"You had a hundred billion chances and ways to have avoided today," Cho says on one video. "But you decided to spill my blood. You forced me into a corner and gave me only one option. The decision was yours. Now you have blood on your hands that will never wash off."