The 27-year-old gunman who shot and killed five students in a classroom at Northern Illinois University last week tried to hide any evidence that would lead investigators to his motive, MyFoxChicago.com reported.
Steven Kazmierczak, a former graduate student, removed the hard drive from his laptop computer and a computer chip from his cell phone and did not leave a note that could help explain why he chose a geology class on Valentine's Day to open fire, police said.
Kazmierczak, who turned the gun on himself after his shooting rampage, also did not talk with anyone about why he was planning the attack.
Jessica Baty, his girlfriend, initially told investigators he had become somewhat erratic in past weeks after he stopped taking his medication but later said that was not true. Police said they planned to talk with Baty again after calling her uncooperative.
Investigators expected to spend at least three more weeks until they release a report on the incident.
The university planned to hold five moments of silence on Thursday at 3:06 p.m., the time of last week's shooting. Each moment will honor the five student victims.
Two funerals were to be held on Wednesday. Gayle Dubowski, 20, was to be remembered at a memorial service in Carol Stream, Ill. Julianna Gehant, 32, who had been a member of the U.S. Army Corps of Engineers, was to be buried with full military honors in Mendota, Ill.
Other victims include Catalina Garcia, Ryanne E. Mace and Dan Parmenter.
Meanwhile, faculty and staff returned to the closed campus on Tuesday for training to help them talk with students about the tragedy.
• Click here for photos of a candlelight vigil.
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