Kirk Spitzer

USA TODAY

TOKYO — A U.S. Navy officer who was arrested Friday on charges of groping and punching a Japanese woman on a commercial air flight from the United States has been released to U.S. custody.

A spokesperson for U.S. Naval Forces-Japan said a Navy lieutenant assigned to Helicopter Maritime Strike Squadron Five One (HSM-51), based at the Atsugi Naval Air Facility, Japan, was handed over to U.S. authorities late Saturday under terms of the Status of Forces Agreement between the U.S. and Japanese governments.

According to Japanese press reports, the officer was arrested in an alleged assault on a 19-year-old female college student while on a flight from San Diego to Japan.

It was the second high-profile arrest of a U.S. serviceman for sexually related offenses in Japan in less than a week and could further complicate efforts to relocate a key U.S. airbase on the island of Okinawa.

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Navy Commander Ron Flanders said the officer, whom he declined to identify further, was being confined to the Atsugi airbase, which is located near Tokyo.

“We are investigating for potential violation of the Uniform Code of Military Justice and if we determine there were violations we will take disciplinary actions that we deem appropriate,” Flanders said.

A 33-year-old U.S. military servicemember was arrested at Narita International Airport early Friday after he repeatedly touched the student – who was sitting next to him on the plane -- on the thigh, then punched her in the head several times, according to Japanese news reports. The alleged assault took place over a period of about 90 minutes. Flight attendants helped the student move to a new seat and reported the incident to police upon arrival in Tokyo.

The incident follows the arrest on March 13 of a 24-year-old Navy-enlisted man on a charge of raping a Japanese woman at a hotel on the island of Okinawa, where about 27,000 U.S. troops are stationed. The sailor remains in police custody on Okinawa. Under Japanese law, suspects can be held for up to 23 days without formal charges.

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Requests for an update on the status of that suspect were not immediately returned Saturday, but it is believed he remains in Japanese police custody on Okinawa; under Japanese law, suspects can be held for up to 23 days without formal charges.

U.S. forces on Okinawa are a key component of the Obama administration’s “re-balance” to the Asia-Pacific region. But crime, noise and congestion associated with the heavy military presence there have long drawn protest from local residents and officials.

Marine Corps Lt. Gen. Lawrence Nicholson met with Okinawa Gov. Takeshi Onaga on Wednesday to apologize in person for the alleged rape. He said the allegations are “a great shame and dishonor” and issued orders forbidding U.S. troops from staying overnight in the capital of Naha, where the alleged rape took place.

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Chief Cabinet Secretary Yoshihide Suga said Monday the arrest was “extremely regrettable” and demanded Washington tighten discipline among U.S. military personnel.

The Abe administration has been locked in a long-running battle with local authorities over plans to move the Futenma airbase to a less crowded part of the island. Onaga wants the base moved off the island entirely and further reductions in U.S. forces there; both sides agreed earlier this month to drop lawsuits over the issue and to resume direct negotiations.

The 1995 arrest and convictions of three U.S. servicemen for kidnapping and raping a 12-year-old girl on Okinawa sparked massive protests and led to negotiations to move the Futenma base and scale back the U.S. military presence. It also led to the resignation of the top U.S. military commander in the Pacific.

Abe has boosted defense spending and tightened security relations with the United States since taking office in 2012 in response to China’s growing military power and assertiveness.

Contributing: Jim Michaels in Washington.

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