Armed with three knives, Mallett entered a building that houses a college and other offices on Wednesday and stabbed four men, the first an employee of Miami-Jacobs Career College, police said. Other people intervened and took away a knife he was using but didn't realize he had more, police said.
Three people were stabbed inside the college's admissions office, and the fourth was attacked outside, Columbus police spokesman Sgt. Rich Weiner said. He said the attack by the 37-year-old Mallett, who had no criminal record in Columbus, appeared to be random.
An aunt in Columbus told police that she thought the suspect was Mallett, Weiner said. She told police he was mentally ill and had been off his medications.
Police video of an officer's response to reports of people being stabbed shows her shooting toward the suspect within seconds of her arrival. Video from Officer Deborah Ayers' police cruiser records her firing multiple shots at a man just 11 seconds after her car stops a few dozen feet from the scene.
A passer-by pointed Ayers in the direction of the suspect, who can be seen briefly in the background.
The video of Wednesday's stabbings shows Ayers stumbling backward after firing several shots and then firing again. An officer coming from the other direction and not seen on the video used a stun gun on the suspect at almost the same time, Weiner said.
Mallett lived in Nashville, Tenn., for 10 years until a month ago, when he moved to Columbus, police said. A message left with family members in Tennessee was not immediately returned Thursday, and a phone for a Columbus family member was not accepting messages.
Nashville police said Thursday that Mallett had a July 2010 conviction for trespassing and a March 2000 conviction for resisting arrest. They had no details. A charge of unlawful possession of a weapon was dismissed in February a year ago, they said.
New York state prison records, which could not be confirmed by authorities on Thursday, show robbery and attempted robbery convictions for a man with the same name, date of birth and race as Mallett.
Two of the victims worked for the college, one was a student and another worked for the attorney general's office, Weiner said.
"There were other people that were trying to subdue this individual, but that's pretty hard to do with somebody who's armed with a couple knives," he said.
Student John M. Desir was in stable condition Thursday, while school employee Donte Dunnagan was in critical condition.
Weiner said attorney Jeff Maloon also was in critical condition, though a message sent to employees at the attorney general's office said Maloon was alert and talking to his family.
Gerald Dowe Jr., also an employee at the school, was treated for minor injuries and was released from the hospital. Weiner said Dowe returned to the building to help officers with their investigation.
Copyright 2013 Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.
The for-profit trade school offers classes in massage therapy, security and investigation, criminal justice and court reporting. It was closed Thursday.