Two people were seriously injured and several suffered minor injuries Wednesday afternoon when a chain-reaction collision happened at M-139 and Empire Avenue in Benton Township.

The Berrien County Sheriff’s Office says at about 1:30 pm, a Medic 1 ambulance was traveling northbound on M139 responding to a priority cardiac arrest call — lights and sirens engaged.

When the ambulance reached the intersection with East Empire Avenue, a Berrien RESA school bus, following the traffic signal but apparently unaware of the approaching emergency vehicle, pulled into the path of the ambulance and the two collided.

The impact of the collision pushed the Berrien RESA Bus into the westbound lanes of Empire and into the path of a westbound First Student bus causing them to collide head on.

The most serious injuries were those of the Medic 1 crew but they were reported as non-life threatening. They were transported to Corewell Health for treatment. The First Student bus driver and assistants also suffered minor injuries. No students were injured.

The Berrien County Sheriff’s Office Crash Investigation unit is still investigating, but they say drugs and alcohol do not appear to be factors in the crash.