A medical helicopter operated by REACH Air Medical Services crashed Monday evening on Highway 50 in Sacramento, critically injuring all three people aboard, according to fire and law enforcement officials.

The crash occurred shortly after 7 p.m. near 59th Street in the eastbound lanes. The craft had recently transported a patient to a hospital and was returning to base when it experienced what officials described as an “in-air emergency.” No patient was aboard at the time of the crash.

Sacramento Fire Department Captain Justin Sylvia said the helicopter appears to have crashed upside down, leaving a debris field across the highway. All three crew members a pilot, a nurse, and a paramedic, were extracted from the wreckage and rushed to area hospitals in critical condition.

One of the injured was trapped beneath the helicopter. According to Captain Sylvia, about 15 bystanders and Sacramento fire crews worked together to lift the aircraft just enough to free her. The helicopter did not catch fire, which officials say may have prevented additional dangers.

Despite the dramatic crash site location, in the center of a busy highway, no motorists were reported injured. “Mind blowing,” Sylvia remarked about the fact that no one on the road was harmed.

The eastbound lanes of Highway 50 were closed in the crash zone, resulting in major traffic disruptions. California Highway Patrol officials confirmed they, along with the National Transportation Safety Board (NTSB) and the Federal Aviation Administration (FAA), are investigating the cause of the crash.

In a statement, REACH Air Medical said it is “keeping all those impacted in our thoughts and prayers” and is working to confirm details of the crew’s condition.

Sacramento City Councilwoman Lisa Kaplan, who happened to be on a ride-along with law enforcement at the time, said she saw plumes of white smoke rising from the helicopter after it crashed. She called the scene “sombering and sobering,” and said it underscored the risks faced daily by medical aviators.

At this time, no official cause has been released, and further details on the victims’ identities and conditions remain pending.