A helicopter flying above Huntington Beach, California, suddenly lost control, spun in the air, and crashed into a row of palm trees near the Pacific Coast Highway, alarming beachgoers. The crash happened on Saturday afternoon.

According to the Huntington Beach Fire Department, five people were hospitalized. Among them were two people who had been in the helicopter and three pedestrians on the ground.

Video captured by witnesses shows the aircraft spinning in midair before plummeting toward the edge of the beach, where it crashed near a stairway connected to the pedestrian bridge.

The helicopter was participating in or connected to a Cars ’N Copters event scheduled in the city.

Authorities, including the FAA and the NTSB, have been notified, and an investigation into the cause of the crash is underway.

As of reporting, casualty details and the condition of the injured have not been fully disclosed.