A senior US official said here on Tuesday that the United States is doing everything possible to ensure the safety of flights in Japan and the security of Japanese residents.

"We are doing everything we can to work closely with our Japanese partners" to investigate a helicopter crash on Japan's southern Okinawa island, deputy State Department spokesman Adam Ereli said at a regular news briefing.

"It is an accident that we have expressed our serious regret over. We have made clear to the government of Japan that we take safety very, very seriously," Ereli said.

A US military helicopter crashed near Futenma Air Station on Japan's southern Okinawa island on Aug. 13, injuring the three crew members.

The accident reignited calls for Futenma base to be moved from a congested residential neighborhood in Ginowan city on Okinawa, which hosts a large portion of the 50,000 American military personnel stationed in Japan.

Okinawa lies about 1,600 kilometers southwest of Tokyo.

Source: Xinhua