The Japanese government lodged a complaint Monday over the resumption of flights of US CH-53D helicopters in Okinawa Prefecture after one crashed at a local university campus earlier this month.

"The government strongly regrets the resumption and conveyed our thoughts to the United States through the Foreign Ministry," Deputy Chief Cabinet Secretary Masahiro Futahashi said at a news conference.

Vice Foreign Minister Yukio Takeuchi told reporters separately that there was a "problem" in US handling of the crash-site investigation and it was "regrettable" the United States did not grant Japanese authorities permission to access the site.

A CH-53D transport helicopter from the US Marine Corps Futemma Air Station crashed at a nearby college campus in Ginowan on Aug. 13, leaving three crew members injured, but causing no casualties on ground.

The US military had refused Japan's request to conduct a joint investigation, and resumed flights of the CH-53D choppers on Sunday. Earlier, it also restarted flight mission of a different type on Friday.

Following the crash, the governments of Okinawa Prefecture and Ginowan City as well as residents reiterated their demand to ground US aircraft and return the base to Japan.

Source: Xinhua