Three individuals are in critical condition at the hospital following a medical helicopter crash on a busy Sacramento highway, as reported by the California Highway Patrol.

Onboard the helicopter were a pilot, a nurse, and a paramedic when it went down Monday night. Bystanders assisted by lifting the helicopter off one of the injured parties, as noted by the Sacramento Fire Department.

Footage of the incident shared by local affiliate KTLA depicts the helicopter plummeting toward the highway, resulting in an impact that filled the eastbound lanes with smoke and debris.

The accident occurred shortly after 7 p.m. local time on Monday, causing significant traffic delays on Highway 50 for numerous miles. As of Tuesday morning, no motorist injuries have been reported.

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.

REACH issued a statement saying, “We continue to investigate the specifics of this incident and assess the condition of the REACH crew involved, who have all been transported to nearby hospitals. No patient was onboard. We thank the community for their concern and support and will provide updates as more information becomes available.”

California officials are still investigating the cause of the crash.