() Three people are hospitalized in critical condition after a medical helicopter crashed onto a busy highway in Sacramento Monday night, according to the California Highway Patrol.

A pilot, nurse and paramedic were aboard the plane when it crashed. A group of bystanders helped lift the helicopter off one of the victims, the Sacramento Fire Department said.

Videos of the crash obtained by local affiliate KTLA show the aircraft diving toward the highway, making impact and filling eastbound lanes with smoke and debris.

The crash, which happened just after 7 p.m. on Monday, brought traffic on Highway 50 to a halt for miles. Officials have not announced any motorist injuries as of Tuesday morning.

The helicopter that crashed is operated by REACH Air Medical Services, local affiliate KTXL reported based on flight radar data.

The company said it was aware of the crash in a statement.

“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. We will continue to provide information as it becomes available. There was no patient on board. We appreciate the concern and support from our community and will share updates when appropriate,” REACH said.

California officials are still investigating the cause of the crash.