SOUTH BEND, Ind. -- Three people, including an Indiana State Trooper, have been hospitalized after a car crash Thursday night.

First responders were called to the intersection of Ireland and Linden roads on South Bend's south side around 8 p.m.

According to Indiana State Police, trooper William Ennis, 32, was on his way to a call to assist the St. Joesph County Sheriff's Department with a car accident when he collided with another car.

Investigators say the driver of that car, Robert Lee Perez, 19, and his passenger Danielle Culter, 20, were headed southbound on Linden Road when they entered the intersection and were struck broadside by the trooper's car.

Officials say the trooper had activated his emergency lights and was traveling westbound on Ireland Road before colliding with the other car.

As a result of the crash, Perez was trapped in the car and had to be extricated by the South Bend Fire Department.

At this time, officials say Perez is listed in critical condition and his passenger, Culter, is listed in serious condition.

Ennis, a five year veteran with Indiana State Police, is stable after suffering injuries to his hip and lower extremities.

The cause of the crash is still under investigation.

ISP officials say they were told that a middled aged white male driving a yellow older model pickup truck with plastic on the rear window had stopped momentarily after the crash.

The ISP would like this man or anyone who witnessed the accident, or may have stopped immediately after the crash, to contact the Indiana State Police Post in Bremen at either (574) 546-4900 or toll free within Indiana at (800) 552-2959.