TOKYO >> Three crew members have been rescued but two were missing Wednesday after a U.S. military helicopter crashed into the sea off Japan’s southern island of Okinawa, Japanese officials said.

The U.S. Army helicopter, a UH-60, crashed about 20 miles east of Kadena Air Base on Okinawa during a flight carrying five crew members, said Japanese Defense Ministry spokesman Kentaro Kato. He said the information initially came from the U.S. military.

Three crew members were rescued, but their conditions were not immediately known, he said. A search was continuing for the two others.

Japan’s coast guard said that it has dispatched patrol boats and aircraft to search for the crew members.

The crash site is possibly near the site of a proposed relocation of the Marine Corps Air Station Futenma on Okinawa, where more than half of about 50,000 American troops in Japan are concentrated. Many Okinawans are opposed to the plan because they want the base completely off the island.