More than 100 police officers, some heavily armed in camouflage uniforms, searched neighborhoods near Central Michigan University on Friday for a 19-year-old student suspected of killing his parents at a dormitory and then running from campus.
The shooting at Campbell Hall happened on a day when parents were arriving to pick up students for the beginning of a week-long spring break.
Police released a photo of James Eric Davis Jr., urging the public to call 911 if they see him but also warning that he shouldn't be confronted. Hours after a campus lockdown, police started a "slow, methodical removal" of staff and students who were ordered to take shelter in campus buildings, Lt. Larry Klaus said.
"He should be considered armed and dangerous," Lt. Klaus said of Mr Davis.
The university identified the two dead as his mother Diva Davis and father James Davis Sr., a part-time police officer in the Chicago suburb of Bellwood. The shooting occurred around 8:30 am at a residence hall at Central Michigan, which is about 112 kilometres north of Lansing.
Lt. Klaus said video at the dorm suggests Davis fled on foot after the shooting. He was wearing a hoodie but had been shedding clothes while on the run.
"This has been a tragic day ... The hurting will go on for a while," said university President George Ross.
The search was focused on Mount Pleasant neighbourhoods near campus.
Officers in camouflage knocked on doors and checked possible hiding places, such as yards and porches. In the surrounding community, some students and staff in the Mount Pleasant school district were told not to leave certain buildings.
Lt. Klaus said Mr Davis was taken to a hospital Thursday night by campus police because of a drug-related health problem, possibly an overdose.
The shooting occurred on the last day of classes before a week-long break. Parents who were trying to pick up students were told instead to go to a local hotel where staff would assist them while the manhunt was ongoing.
The school posted an alert on Friday morning on social media about shots being fired at Campbell Hall and an automated phone message was sent to students.
Halie Byron, 20, said she locked herself in her off-campus house, about a 10-minute walk from the dorm. She had planned to run errands before traveling home to southeastern Michigan.
"It's scary thinking about how easy a shooter can come into a college campus anywhere — a classroom, a library. There's so much easy access," Ms Byron said.