(FOX40.COM) -- The circumstances behind a helicopter crash that shut down a freeway in Sacramento and sent its passengers to a hospital in critical condition are still under investigation. • Video Above: Helicopter crash shuts down Highway 50 in Sacramento

Around 7 p.m. on Monday, a REACH Air Medical Services helicopter that was carrying three passengers plummeted from the sky into the busy Highway 50. REACH provides critical care air and ground transport services to communities throughout California, Nevada, Oregon, Colorado, and Wyoming.

Remarkably, the chopper did not crash into any vehicles, and no other injuries outside of the helicopter's passengers were reported.

The crash comes amid a massive ongoing construction project happening on Highway 50.

Injuries

First responders said

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