The crash happened Wednesday night at North Island Naval Air Station, near San Diego, the U-T San Diego reported.
Navy spokesman Lt. Aaron Kakiel said the helicopter was an MH-60R Seahawk, and described the crash as a hard landing, injuring the four crew members aboard.
The injured were taken to a nearby hospital, but their conditions were not immediately known, Kakiel said.
Other news media reported a small fire broke out after the crash, but Kakiel did not give any details on the fire.
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