Officials are investigating after a medical helicopter crashed on a Sacramento freeway Monday evening.

The Sacramento Fire Department said a REACH medical helicopter went down shortly after 7 p.m. on eastbound Highway 50 near 59th Street.

Three crew members — a pilot, a nurse and a paramedic — were on board and all were taken to area hospitals with critical injuries, Captain Justin Sylvia with Sacramento Fire said. No vehicles on the freeway were involved.

Two crew members were located in the roadway while one of the crew members was trapped under the helicopter when the first unit from the fire department arrived, Sylvia said. A fire captain and bystanders who offered help were able to lift the aircraft off the trapped crew member.

“We are in the process of determining the details of this situation, as well as the condition of the REACH crew involved, who were all taken to area hospitals,” REACH said in a statement. “We will continue to provide information as it becomes available. There was no patient on board.”  

One lane of Eastbound Highway 50 had been reopened at 59th Street to allow for traffic to pass through, the California Highway Patrol said.

Video obtained by CBS Sacramento from a person inside a vehicle in the westbound lanes of the highway captured the moment the helicopter went down. A photo taken by a CBS Sacramento crew at the scene shows the helicopter upside down across multiple lanes covered in debris.

The cause of the crash remains under investigation. The Sacramento County Sheriff’s Office said it is assisting the CHP, which said it will help the National Transportation Safety Board in the probe. CBS Sacramento has reached out to the Federal Aviation Administration as well.