Portland police are investigating the death of a 22-year-old Portland man who was involved in a three-car crash Saturday afternoon at the intersection of Brighton Avenue and Riverside Street.

Police are not classifying the death of Patrick Lobor as a traffic fatality, but have not released additional details about how they believe he died.

Lt. Robert Martin said a person driving one of the cars got out of his car, stumbled to the middle of the intersection and collapsed, according to News Center Maine (WCSH/WLBZ). He was found dead by first responders.

Police say the crash happened about 1:30 p.m. when a car hit two others that were stopped at a traffic light on Brighton Avenue. Two people in one of the other cars involved in the crash were taken to the hospital with minor injuries and have since been released. Police did not release their names Saturday night.

Lobor’s body will be taken to the state Medical Examiner’s Office for an autopsy Sunday that is expected to determine the cause of death, police said.

The intersection of Brighton Avenue and Riverside Street in Portland was closed Saturday while police were investigating the incident.

Martin is asking anyone who witnessed the crash to call police at 874-8575.

“We believe there are at least two more witnesses who could provide us with crucial information to determine what happened,” Martin told News Center Maine.