Japanese police arrest US Marine in Okinawa over alleged robbery and killing of local woman

Japanese police have arrested a 20-year-old US marine over the alleged robbery and killing of a woman in Japan's Okinawa prefecture.

It is the latest criminal case on the southern island where the heavy American troop presence has remained a sensitive issue.

The Okinawa prefectural police said on Sunday they arrested a marine from the Futenma Air Station on suspicion of killing a 39-year-old local woman at a hotel in Naha, Okinawa's capital city, and taking her wallet and backpack in the early hours of Saturday.

Kyodo News agency, citing the police, reported the woman's body was found in her hotel room and she appeared to have been strangled to death.

Police said security camera footage showed the suspect entering the hotel with the victim and coming out alone.

An officer arrested the suspect after spotting him walking alone on a street in Naha's entertainment district late Saturday, Kyodo said.

"The case deals a major shock and adds fear to the Okinawans who have already been forced to live next to US bases," newly elected Okinawa Governor Genta Koja told reporters.

"I must say, discipline and troop education are not working at all," said Mr Koja, referring to the US military's measures taken in response to past criminal cases.

Some 50,000 US troops are deployed in Japan under a bilateral security pact, about half of them on Okinawa, whose strategic role is seen as increasingly important for the Japan-US military alliance amid growing tensions with China.

Okinawans have long complained about noise, pollution and crime related to US bases, with crimes involving US service members on Okinawa complicating ties between Japan's central government and the Okinawa administration.

The latest case comes as Prime Minister Sanae Takaichi's cabinet pushes to further fortify its Japanese military presence on Okinawa and work more closely with the US military.

She said her government had strongly protested to the US side and demanded maximum cooperation with the Japanese authorities in the investigation, as well as tougher discipline for US service members and preventive measures.

The US Marine Corps said in a statement the suspect was assigned to the III Marine Expeditionary Force on Okinawa and that it was fully cooperating with Japanese authorities.

"The Marine Corps takes these allegations very seriously and expects every Marine to adhere to the highest standards of behaviour," it said.

Futenma base, located in a densely populated area in central Okinawa, has been a sore spot for many Okinawans for decades, who demanded its relocation.

Despite protests, the central government green-lit construction to relocate the base to Henoko on Okinawa's eastern coast, though the project has faced massive delays.

A high-profile 1995 rape of a 12-year-old girl by three US service members sparked massive protests against the heavy US troop presence on Okinawa.

The number of arrests related to US service members and their families exceeded 100 last year, according to prefectural police.