Tokyo - Rescuers were scrambling Thursday to find a US marine pilot who went missing after a jet crashed off the southwest coast of Japan.
The pilot ejected from the Marine F/A-18 before it plunged into the sea on Wednesday evening, but the marine's whereabouts are unknown.
The US and Japanese military said they expanded their search on Thursday following the accident, which happened some 90km off the coast of southwestern Kochi prefecture.
"Search and rescue efforts for the pilot who ejected from a Marine F/A-18 December 7 have expanded to a greater radius and include more rescue assets as the daylight increases," the Marine Corps said in a statement on Thursday.
"The bilateral search and rescue efforts continued through the night with the US military working closely with" Japan's Self-Defence Forces, it added.
Japan has dispatched four ships and eight planes to assist in the rescue operation, it said.
Another jet was also flying on the same mission, Japan's defence ministry said.
The crashed plane is assigned to the US Marine Corps Air Station Iwakuni, one of the main US military bases in Japan, which hosts tens of thousands of US military personnel.
The accident comes as US defence secretary Ashton Carter visits Japan as part of his last Asian tour.