This U.S.-made shell believed to be from World War II was found near Ejina Island in Itoman city, Okinawa, Feb. 11, 2024. (Itoman city)

Japanese troops on Wednesday detonated eight unexploded, U.S.-made bombs believed to be from World War II off the coast of southern Okinawa.

The ordnance — one 5-inch shell, one 4-inch shell, five 3-inch shells and one M60 white phosphorous shell — were detonated in waters near Kitanashiro beach in Itoman city, about 3,200 feet west of Ejina island, according to a spokesman for the city.

The operation was originally scheduled from 9 a.m. to 11:50 a.m., the city announced in a Jan. 20 news release, but finished it earlier than expected, a spokesman for the city’s Disaster Prevention Section said by phone Wednesday.

Members of the Japan Maritime Self-Defense Force carried out the operation safely underwater, he said.

Boats were evacuated to a radius of 984 feet, and swimming was prohibited within a radius of nearly two miles, according to the release. Traffic was not restricted.

The evacuation and restrictions were lifted at 11:02 a.m., the spokesman said.

Japan coast guard and fire department officials kept watch from the surrounding waters, according to the release.

The 5-inch shell was found Dec. 5, 2023, near Churasan beach in Tomigusuku city, an Itoman city spokesman said by phone Tuesday.

Four 3-inch shells and one 4-inch shell were found Feb. 11 near Ejina Island. The fifth 3-inch shell and the white phosphorous shell were found July 14 near Okaha island in Itoman, the spokesman said.

He declined to provide details on how they were found.

Some Japanese government officials speak to the press only on condition of anonymity.

Last week, Japanese troops removed and defused a 5-inch, U.S.-made WWII shell found in November at a construction site in the Matsuyama district of Naha city. Another 5-inch, U.S.-made shell found in October was removed from the Uebaru district and defused in December.

The Japanese government has ramped up searches for unexploded ordnance at airports across the country. The government began surveys in October at Miyazaki Airport on Kyushu, the southernmost of Japan’s four main islands, after a WWII-era bomb exploded that month on a taxiway.

Magnetic surveys began in December at Naha Airport, along with airports in Sendai, Matsuyama and Fukuoka.

Crews disposed of nearly 22 tons of unexploded ordnance leftover from WWII on Okinawa between April 1, 2023, and March 31.

Stars and Stripes reporter Keishi Koja contributed to this report.