Police identified the 43-year-old man who killed three students and wounded five at Michigan State University, saying Tuesday that a tip from the public led to a confrontation with officers miles from campus, where the gunman fatally shot himself.

Investigators still were sorting out why Anthony McRae fired inside Berkey Hall and the MSU Union — a popular place to eat and study — shortly before 8:30 p.m. Monday. The shootings led to a campus lockdown and a manhunt that ended roughly three hours later.

"We have absolutely no idea what the motive was,'' said Chris Rozman, deputy chief of campus police, adding that McRae was not a student or Michigan State employee. He said police confronted McRae before he killed himself.

Overnight, the school announced that all campus activities, including athletics, were canceled for at least 48 hours. This would affect the men's basketball team, which was scheduled to host Minnesota on Wednesday at 7 p.m. ET, and the men's tennis team, which was scheduled to host Drake on Wednesday at 5 p.m. ET.

It was unclear if the women's basketball team, which is scheduled to play at Purdue on Wednesday night, would be impacted.