(Mass.gov)

YOKOTA AIR BASE, Japan — A home-made cannon likely fired “projectiles” at Yokota Air Base on Thursday night, according to U.S. and Japanese officials.

Residents near the base, which serves as headquarters for U.S. Forces Japan, reported explosions at about 11.30 p.m., according to a Tokyo Metropolitan Police spokesman.

Police found two metal pipes, lead wire and a battery in an empty lot about 350 meters east of the base. Partly buried, the pipes pointed toward the base, said a spokesman for Tachikawa Police, which initially responded to the calls.

Yokota spokesman Capt. Ray Geoffroy confirmed the discovery of improvised launching devices near the base but said there are no reports of injuries or damage.

Jonathan Revell, 38, of Smyrna, Tenn., said he heard two loud bangs Thursday night from his home on the east side of the base. He went outside to investigate but didn’t hear any emergency vehicles responding.

“I thought it was kind of odd to hear fireworks at 11 p.m.,” he said. “I’ve been here a little over two years, and it’s the first time I’ve heard anything like that.”

Police and U.S. military officials have been searching for any “projectiles” that may have been fired, but none had been found as of Friday morning, the spokesman said.

There was no immediate claim of responsibility, the spokesman said.

An anti-U.S. military, left-wing extremist group known as Kakurokyo has carried out similar attacks. The group is thought to be responsible for home-made mortar rockets found in November 2009 just outside Yokota and December 2009 near Naval Air Facility Atsugi.

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