A U.S. sailor at Camp Pendleton in California who was critically injured Wednesday when he was struck by a helicopter’s rotor blade died early Saturday morning.

Military officials said the unidentified service member succumbed from his injuries at Scripps La Jolla Medical Facility, the Orange County Register reported.

The accident happened at 6:10 p.m. Wednesday at Marine Corps Air Station Camp Pendleton, the newspaper reported.

Details about how the accident occurred have not been released, but an investigation was underway, a military official told the paper.

The aircraft was a UH-1Y Venom, the report said.

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