US Navy today said it has called off a search for three sailors missing since a transport plane crashed in the Philippines Sea south of Japan on Wednesday en route to the USS Ronald Reagan aircraft carrier. <br/><br/>The US Seventh Fleet said in a press release that during the course of two days, eight US Navy and Japan Maritime Defence Force ships, three helicopter squadrons and maritime patrol aircraft covered nearly 1,000 square nautical miles. <br/><br/>It said it is investigating the cause of the crash. Eight other people were rescued shortly after the aircraft crashed. The plane was on a routine transport flight, carrying passengers and cargo from Marine Corps Air Station Iwakuni in southern Japan to the USS Ronald Reagan.