(CNN) -- A Wayne State University officer is on life support after he was shot in the head during a police stop on Tuesday night.
A suspect, which police also described as a person of interest, is in custody but has not been charged with the crime, according to Wayne State University Police Chief Anthony Holt.
Collin Rose, 29, is the fifth police officer shot in the US in less than a week.
Rose was on a neighborhood patrol near the Wayne State University campus, which has recently seen a rash of auto crimes. He saw a subject on a bike approach the area, and he called for backup, Holt said.
When the backup officer arrived on the scene, he found Rose with a gunshot wound to the head. The circumstances surrounding the shooting are unclear.
"I can't sugarcoat this," Wayne State University President Roy Wilson said at a press conference.
"This is a tragedy of immense proportions, something that Wayne State fortunately rarely has to experience."
The person in custody is being held on outstanding misdemeanor warrants, one from 2011 and another from 2014, according to Holt.
Wayne State University police encountered the suspect a few years ago. In one incident, the suspect was blocking traffic in the middle of the street and refused to leave. There was a scuffle with police, and one of the officers involved sustained minor injuries, according to Holt.
Working on a Master's degree and an upcoming wedding
Rose is a five-year veteran of the Wayne State University police force and works as a canine officer.
"Not only is he a canine handler, he's very, very involved in the community. He goes to schools. He gives out demos," Holt said. "He's just an outstanding, proactive officer."
A couple of months ago, Rose organized a memorial for slain Detroit police officer Patrick Hill. Rose named one of his dogs, Wolverine, after officer Hill, according to Holt. Rose is one credit away from finishing his Master's degree in Police Administration from Wayne State University. He's engaged to be married in October 2017.
The gun used to shoot Rose hasn't been found. The Detroit Bureau of Alcohol, Tobacco, Firearms and Explosives is offering a $5,000 reward to anyone with information regarding the weapon.
This shooting follows a violent few days for police officers across the country. On Sunday night alone, four officers were shot while on duty, one fatally.