COLUMBUS, Ohio—A triple-shooting investigation on the Ohio State campus remains open after two university employees die and another is injured after officials say one of those employees opened fire after a poor performance review.

NBC 4 reports with the FAST FACTS from local authorities.

Three university employees were shot during an incident at a maintenance building on campus early Tuesday morning. Two employees were killed, one of whom was the suspect, and one employee remains in stable condition.

Officers were called to 2000 Tuttle Park Place, near Ohio Stadium, around 3:30 a.m. One employee was pronounced dead at the scene, and two other employees were transported to the Ohio State University Medical Center Main. One victim was in critical condition, and one was stable. Authorities said the suspect was in police custody.

Nathaniel Brown, 51, was the shooting suspect. Brown’s title was custodial worker. He had been with the university since Oct. 2009 and was a probationary employee. Denton said Brown sustained a self-inflicted gunshot wound at the scene. Brown was found in the garage, multi-use kind of area, where the shooting occurred.

Brown was treated at the scene and transported to OSU Medical Center Main. Brown was pronounced dead after 7 a.m. Tuesday.

“More than half a dozen employees of the facility’s operation division were working at the maintenance building when the suspect entered the office suite with a gun and began shooting,“ Denton said. “Nathaniel Brown had a poor performance evaluation and came back to initiate this incident.“

Officials said Brown was scheduled to work this morning and walked in wearing dark clothing and carrying two firearms.

Officials said students weren’t in danger at any point during the incident.

SUSPECT’S PERSONNEL FILE

Documents from Brown’s personnel file showed that supervisor’s complained that Brown was tardy, slept on the job and had problems following instructions. The university sent him a letter on March 2, informing him that his employment was to end Saturday.

The file included hand-written notes about Brown’s work at the university that paint a picture of a difficult employee who sometimes displayed bizarre and hostile behavior. Specific notes in the file describe an evening where supervisors checked up on Brown. When they found him, Brown apparently asked the managers what they were doing and appeared to threaten to pull a knife on them, according to the personnel records.

Residents who lived near Brown on Grasmere Avenue told NBC 4 they were shocked and added that Brown kept to himself.

UNIVERSITY RESPONSE

Campus and Columbus Police officers surrounded the maintenance building and the area of McCracken Power Plant for about 45 minutes after the 911 call.

The shooting prompted mass communication between the university and students.

Officials sent an emergency text alert about the shooting at about 4:22 a.m.

The message alerted subscribers, “Shooting near McCracken Power Plant. Suspect in custody. All is safe. Avoid area.“

“I’m extremely satisfied and appreciative of the way the staff responded, notified and took cover,“ Baisden said.

The university continued normal operations Tuesday.