Nathaniel Brown was days away from losing his job when he opened fire with two handguns early Tuesday in a maintenance building at the nation's largest university, police said. No students were hurt.

Brown, 51, had a criminal history that included serving about five years in prison on a charge of receiving stolen property, records show. He lied about it on his job application, and it wasn't immediately clear whether Ohio State had completed a background check on him.

Ohio State released documents from Brown's personnel file showing that supervisors complained he was tardy, slept on the job and had problems following instructions. The university sent him a letter March 2 informing him that his employment was to end Saturday.

Brown had been scheduled to work his normal third shift Tuesday, campus Police Chief Paul Denton said. Brown arrived for work dressed in dark clothing, wearing a hooded sweat shirt and a backpack. Police didn't say what was in the backpack. About a half-dozen other employees were in the building when the shooting began about 3:30 a.m.

Denton called the shooting work-related but didn't describe a motive.

Police tactical units surrounded the building and found Brown with a self-inflicted gunshot wound in a garage bay, Denton said. He was pronounced dead at a campus hospital hours later.

One of the victims, building services manager Larry Wallington, 48, died at the scene. The other, shift leader Henry Butler, 60, was in stable condition at Ohio State University Medical Center, officials said.

Butler wrote a letter Feb. 11 recommending that Brown be terminated, according records released by the university. Even though colleagues had made a special effort to help Brown, he was not improving, the letter said.

Brown was hired in October and was still on probation. He had recently complained to a union representative that his supervisors were being unfair in their evaluation of him, said Richard Murray, president of Communications Workers of America Local 4501, which represents custodial workers at Ohio State.

"He was frustrated and upset, certainly. But he didn't make any threats or anything," Murray said. The union couldn't do more with the case because Brown didn't file a formal complaint, he said.

Denton declined to say whether other employees were targeted.

Brown was released from prison in 1984, records show. The case file had been archived, and more information on the crime wasn't immediately available, prisons spokeswoman Julie Walburn said.

On his job application, Brown checked "no" when asked whether he had ever been convicted of a felony or misdemeanor. A letter from Ohio State offering him the job said it was contingent on a satisfactory criminal background check.

Vernon Baisden, assistant vice president for public safety, declined to comment on whether the check was completed. Ohio State's policy on background checks depends on the job, he said.

Both shooting victims had worked for the university for about 10 years. Family members reached Tuesday declined to comment.

Classes went on as scheduled Tuesday. More than 55,000 students attend the main campus in Columbus. The maintenance building is next to a power plant and across the street from Ohio Stadium, home to the university's football team.

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