TOKYO (Reuters) - An American man working at a U.S. military base in Japan was arrested on Thursday on suspicion of dumping the body of a 20-year-old Japanese woman, police said, a case likely to stir anti-U.S. sentiment ahead of a visit by President Barack Obama.
The 32-year-old civilian working at the base on the island of Okinawa admitted to abandoning the corpse but did not make any comments about whether he had killed the woman, an Okinawa police spokesman said.
Japanese Foreign Minister Fumio Kishida summoned Caroline Kennedy, U.S. ambassador to Japan, to lodge a protest.
"I expressed a strong regret to Ambassador Kennedy and lodged a stern protest. I told her an incident like this is inexcusable and that I feel strong indignation," Kishida told reporters.
Kennedy told Kishida the United States would redouble its efforts to prevent similar incidents, the foreign minister said.
In Washington, the Pentagon said the individual was a contractor, but did not name him.
Spokesman Peter Cook said the Pentagon would provide "complete cooperation" in the investigation, while State Department spokesman John Kirby expressed condolences.
"This is a terrible tragedy and it's obviously an outrage," Kirby told a daily news briefing. "We're treating this situation with the utmost seriousness."
Obama, who is to attend a Group of Seven summit in Japan next week, will become the first U.S. president to visit Hiroshima, a city destroyed by a U.S. atomic bomb 71 years ago.
Okinawa, the site of a bloody World War Two land battle, hosts the bulk of U.S. military forces based in Japan since the war, and many residents resent what they see as an unfair burden.
U.S. installations take up about 18 percent of Okinawa's land area and past incidents involving Americans have fueled resentment.
In 1995, a 12-year-old schoolgirl was raped by three U.S. servicemen on Okinawa, sparking huge protests, and earlier this year, a U.S. sailor was arrested on suspicion of raping a woman at a hotel in Naha in the south the island.
Japan's ambassador to the United States, Kenichiro Sasae, said he hoped the latest incidents would not affect the mood toward Obama's visit to Hiroshima, as the Japan-U.S. alliance had made "tremendous progress" under the current U.S. president.
"The Okinawa issue is the Okinawa issue," he told reporters. "This is a tragic event, but a tragic event should not overshadow the fundamental objective of the alliance – that's what I hope," he told reporters in Washington.
(Reporting by Kiyoshi Takenaka; Additional reporting by Doina Chiacu, Idrees Ali and David Brunnstrom in Washington; Editing by Andrew Hay and Sandra Maler)