The Pentagon’s inspector general has initiated a review of how U.S. military personnel in Japan complied with policies on preventing and addressing violent crimes after reports of sexual assaults in the country.

"Specifically, we will examine the performance, training, and criminal history of service members who committed violent crimes against Japanese nationals,” said Randolph Stone, assistant inspector general for evaluations of space, intelligence engineering and oversight, in a Sept. 2 memo announcing the probe.

Analysts will perform evaluations at U.S. Forces Japan, Yokota Air Base; U.S. Army Japan, at Camp Zama; U.S. Naval Forces Japan, Yokosuka; U.S. Marine Corps Forces Japan, headquartered at Camp Courtney; and 5th Air Force and U.S. Space Force, both headquartered at Yokota Air Base, he wrote.

The IG started the evaluation on its own instead of directed by Congress, said Mollie Halpern, spokesperson for the inspector general’s office.

About 60,000 U.S. military personnel are based in Japan.

U.S.-Japan relations have been rocked since the Japanese government protested to the U.S. Embassy about at least two alleged sexual assault cases in recent years involving American service members on Okinawa. One case involved an Air Force service member accused of assaulting a 16-year-old girl in December 2023 while another from May 2024 involved a Marine accused of assaulting a 21-year-old woman.

A Japanese court in June found the Marine guilty of sexual assault in the 2024 case and sentenced him to seven years in prison, according to an Associated Press report.

U.S. Forces in Japan announced in July 2024 measures to prevent sex crimes, including conducting joint patrols with Okinawa police, strengthening sobriety checkpoints, and establishing a forum where the U.S. military and the prefecture could exchange views, according to the Asahi Shimbun.