Sasebo naval base was briefly locked down Thursday after reports of gunshots, but operations soon returned to normal after evidence of an active shooter and casualties failed to turn up, the U.S. Navy said in an official tweet.
Gunshots were reported heard coming from a building that apparently hosts a mine countermeasures squadron on the base in Nagasaki Prefecture on Thursday morning. The base was put on lockdown as a precaution and the building was checked by security, said Darin Wilson, Deputy Public Affairs Officer for U.S. Naval Forces, Japan.
The tweet, sent about 12:15 p.m., said that all was clear at Sasebo and the base had returned to normal activities.
"The area that this incident happened in is a maintenance area — not the quietest place on base," Wilson was quoted as saying by the Stars and Stripes newspaper. "Someone thought they had heard something. Sounded like a gunshot."
U.S. troops have been stationed in Japan since its defeat in World War II. Occasional crime by U.S. personnel or civilian base workers infuriates the public and often spurs calls for the bases to go.