The arrest of a US Marine in Okinawa sparked a wave of protests over military crimes.

For many Okinawans, the arrest of a U.S. service member accused of robbing and killing a woman in a hotel room has reignited decades of anger over crimes committed by U.S. troops on the island.

"Honestly, my first reaction was: 'Again?' — 52-year-old Ai Sato, who has lived in Okinawa for a long time, told the BBC. “Nothing has changed since my childhood.” How many times will we repeat the same thing, create new victims, cause suffering to their families, and ultimately cause grief to the people of Okinawa?”

Akemi Oshiro, 62, a resident of Ginowan, echoed those sentiments.

"I know we shouldn't get used to such terrible things, but because they keep happening I've stopped being surprised," she told the BBC.

The US military presence in Okinawa is the largest in Japan. There are several American military bases and tens of thousands of US military personnel stationed here.

US Marine Corps soldier Devin Jacob Ballard, 20, was arrested on Sunday. An investigation is ongoing, police said; Ballard is in custody in Japan because the offense he is charged with is not related to the performance of official duties.

Whether a U.S. military member is acting on duty, off duty, or off duty determines whose jurisdiction he or she falls primarily under.

When Japan has jurisdiction but the suspect is in U.S. custody, the U.S. side can hold the suspect until Japan files charges.

Ballard was assigned to the III Marine Expeditionary Unit and stationed at Futenma Air Force Base in Ginowan.

Anna Yagi, 39, was found dead early on Oct. 3 in a hotel room in Naha, the capital and largest city of Okinawa prefecture, police said.

CCTV footage reportedly shows a man (presumably the suspect) entering the hotel with a woman and then leaving alone with her belongings. Local media, citing police, report that Yagi was apparently strangled with a cord.

Japanese Prime Minister Sanae Takaichi sent an official protest to Washington. However, some residents, including Sato, believe this is not enough.

“I'm deeply disappointed by the same government statements that we've been hearing for decades - that they will protest or that they take this matter seriously,” she said. “I want Prime Minister Takaichi to call President Trump directly—a man with whom she has said she has a close relationship—and discuss concrete measures to prevent this from happening again.”

Following news of the killing, about 100 people protested in Naha and Tokyo, and others in Japan took to social media to express their outrage and demand justice; one user wrote: “Enough!”

Over the past few years, a series of accidents and crimes have resulted in growing opposition to the US presence on the island.

The rape and murder of a 20-year-old local woman in 2016 sparked demonstrations by thousands against the significant US presence in the region. The former US Marine was subsequently sentenced to life in prison for the crime.

There are currently about 55,000 American troops stationed in Japan, with the largest concentration in this tropical island prefecture. Okinawa is one of the country's smallest prefectures in terms of area, but it is here that 70% of Japanese territory is used exclusively by the US military.

In 1972, Okinawa Prefecture was returned to Japanese control after the islands were occupied by the US military at the end of World War II. Since then, there have been 6,409 arrests in connection with crimes committed by US military personnel, according to the Okinawa Prefectural Government.

Locals say the large U.S. presence has fueled resentment over a range of issues, from crime including rape, assault and accidents involving drunk drivers to public order disturbances such as noise and plane crashes.

In 1995, three American soldiers kidnapped, beat and raped a 12-year-old schoolgirl on her way home from an office supply store.

"Even 80 years after the war, Okinawa, where we live, remains a turbulent place," Hitomi Miyagi, 48, a mother of two boys, told the BBC. “We will not stop speaking our minds in the hope that Okinawa will become a place where we can live in peace.”