US Coast Guard and military crews are searching for five crew members of a UH-60 Black Hawk, the Coast Guard said in a news release Wednesday.
Officials at Wheeler Army Airfield near Honolulu reported losing communications with the crew on Tuesday night around 10 pm.
Responding teams reported spotting a debris field about 2 miles (3 km) west of Kaena Point, Oahu.
The UH-60 Black Hawk is a four-bladed, twin-engine utility helicopter manufactured by Sikorsky Aircraft.
This is the second major crash the US military has experienced this month.
Earlier this month, three US service members died after a US military aircraft crashed off the east coast of Australia. Twenty-three of the 26 personnel aboard the MV-22 Osprey were rescued.
The aircraft was in Australia for a joint military training exercise held by the US and Australia last month in Shoalwater Bay.