Authorities are investigating the discovery of an old Japa­nese grenade, apparently live, that was found Sunday beneath a park bench near the Fort DeRussy Chapel.

"Somebody that was attending the chapel at about 11 in the morning saw this object under one of the park benches and called it in to the security down there," said Dennis Drake, a spokes­man for U.S. Army Garrison Hawaii.

Drake said Army Explosive Ordnance Disposal experts responded, "and it was determined that it was a Japa­nese hand grenade."

Officials cordoned off the area as the grenade was checked out. Drake said the grenade was turned over to the FBI.

"They thought they had a second device, but it was actually just a backpack that was full of papers," Drake said.

Bomb-sniffing dogs swept the area, and by about 3:40 p.m. the area was reopened, he said.

Officials said it is a mystery how or why a Japa­nese grenade came to be found under the park bench. Drake said the grenade was not buried.

Tom Simon, an FBI spokes­man in Hono­lulu, said the bureau is jointly investigating the discovery along with the U.S. Army Criminal Investigation Command and the Bureau of Alcohol, Tobacco, Firearms and Explosives.

Simon declined to discuss specifics of the find. He said no one has been arrested.

"At this point we’re not going to talk about the evidence in the case in the media," he said. "We’ll pre­sent our evidence in court."