TOKYO: Japanese police are probing allegations that a US serviceman assaulted a teenager after breaking into his home in Okinawa, reports said on Friday, despite a nationwide military curfew.

The allegations come just weeks after the United States put all 47,000 of its military staff stationed in Japan—both in Okinawa and elsewhere—under an indefinite nighttime curfew in response to the alleged rape of an Okinawan woman by two US servicemen. The pair were arrested last month.

The rape case stoked already high tensions in Okinawa, which has seen angry demonstrations against the US deployment to the island of the tilt-rotor Osprey aircraft, which local activists charge has a poor safety record.

On Friday, public broadcaster NHK and other Japanese media said that the unidentified 24-year-old serviceman entered an apartment above the village pub where he had been  drinking and then slapped a teenage resident.

The soldier, who allegedly became violent at the bar before the incident early on Friday morning, then jumped out the home’s third-floor window, sustaining injuries that required hospitalization, reports said.

Police in Okinawa could not immediately confirm the reports.

Foreign Minister Koichiro Gemba described the alleged incident as “outrageous”, with Jiji Press news agency reporting that US ambassador to Japan John Roos would be summoned to the foreign ministry later on Friday.

Following the arrest of two US naval personnel, both 23, on charges of raping and injuring a woman last month, US Assistant Secretary of State Kurt Campbell issued a “heartfelt apology” for the incident which he  called “profoundly, deeply regrettable”.

Okinawa is home to around half of the US troops stationed in Japan under a treaty signed after World War II, when Tokyo was stripped of the right to wage war.

The heavy troop presence has long fuelled resentment against both Tokyo and Washington in Okinawa, which was under US control from 1945 to 1972.