A U.S. sailor from the Sasebo Naval Base in Japan was found dead Sunday morning in a train station in the city.

The U.S. sailor, identified by Japanese police as Petty Officer Lewis Stiles, 25, was found dead around 5 a.m. Sunday local time in the Haiki station in Sasebo, Stars And Stripes reported.

Stiles had a head injury and local media reported that the sailor climbed on top of a train and was electrocuted by an overhead power line, Nagasaki police told the Japan Times. Sasebo is a city in the Nagasaki Prefecture.

Five empty cans of Chuhai, a Japanese cocktail, were taken from the Haiki train tracks where the U.S. sailor was found dead, the Japan Times reported.

The paper said Stiles had a “bloody head wound.”

The sailor’s death is under investigation. Stars And Stripes reported that Stiles’ body was found face-down by police.

“There will be an investigation, obviously,” Jon Nylander, spokesman for Commander Naval Forces, told the paper.

A check of the Sasebo station when it closed Saturday night indicated the sailor was not in the station at that time.

It’s unclear whether Stiles violated a curfew, which the U.S. Navy instituted Oct. 19. The 11 p.m. to 5 a.m. curfew is in effect following an alleged assault and rape of a woman from Okinawa, according to Stars And Stripes.

CNN reported that the time the U.S. sailor’s body was found may mean he violated the curfew.

The network noted that Stiles was not wearing his Navy uniform.

The U.S. sailor’s death is being investigated as either an accident or a crime, according to CNN.