The U.S. Marine Corps in Okinawa said Tuesday it will resume flight operations of its CH-53E transport helicopters from the next day after having kept them grounded following the crash-landing of one of them in the prefecture about a week before.

Lt. Gen. Lawrence Nicholson, the commanding general of U.S. Marine Corps Forces in Japan, is "satisfied that the CH-53E aircraft is prepared to return to safe flight operations," the Marines said in a press release, adding that the decision was "not taken lightly."

U.S. military chopper bursts into flames on landing in Okinawa

U.S. military to ground CH-53 helicopters after accident in Okinawa

"It's extremely deplorable the Marines have made the announcement in a one-sided manner, without sufficiently explaining about the safety (of the aircraft)," Defense Minister Itsunori Onodera told reporters in Tokyo.

Okinawa Deputy Gov. Moritake Tomikawa told a senior member of the U.S. Marine Corps over the phone that resumption of the flights is "totally unacceptable," according to the local government.

A press release issued by the Marines in Okinawa said Lt. Gen. Lawrence Nicholson, the commanding general of U.S. Marine Corps Forces in Japan, is "satisfied that the CH-53E aircraft is prepared to return to safe flight operations" and that the decision was "not taken lightly."

"Aviation experts have conducted a thorough review of the maintenance records and found no issues with the standard maintenance practices, actions, technical directives, periodic inspections and no operational matters to warrant concern," it said.

In the accident last Wednesday, the large transport helicopter burst into flames as it made an emergency landing near the U.S. military's Northern Training Area on the main island of Okinawa.

None of the seven crew members or local residents was hurt in the accident. But the site in the village of Higashi was a few hundred meters away from residential homes, rekindling concerns over the risks locals face for living close to U.S. military facilities.

Nicholson directed a 96-hour operational pause Thursday morning for all the CH-53E helicopters stationed in Okinawa, but Okinawa Gov. Takeshi Onaga had demanded the aircraft be grounded until the cause of the accident is identified and "effective" preventive steps are taken.

The press release did not explain the cause of the accident and on preventive measures.

"We take the safety of our aircrews and the citizens of Okinawa seriously," Nicholson was quoted as saying. "The CH-53E is a reliable aircraft that has served this alliance successfully for many decades here on Okinawa and in mainland Japan."

Earlier in the day, the local assemblies of the village of Higashi and the city of Ginowan, which hosts U.S. Marine Corps Air Station Futenma, unanimously adopted resolutions protesting the accident.

At the accident site, officials of the Japanese Defense Ministry's local bureau and the Okinawa prefectural government entered the restricted zone set by the U.S. military to conduct radiation surveys as locals have expressed concerns over the radioactive material said to be used in parts of the helicopter.

The Marines told Kyodo News on Sunday that radioactive material has been removed from the helicopter and that it is not used at a level that could affect health. They did not disclose what radioactive substance was used and how much.

The CH-53E in question belongs to the Futenma base. The accident follows the crash-landing of a U.S. military Osprey aircraft off the main island of Okinawa in December, which was also based in Futenma.

Onodera had earlier said Japan expects the U.S. military to suspend CH-53E flights in Okinawa for an "indefinite period" until safety is ensured.

Onodera, meanwhile, told reporters in Tokyo on Tuesday that he will ask the U.S. military to refrain from conducting a missile countermeasure exercise over land in which aircraft deploy decoy flares, citing safety concerns among local residents.

The U.S. military has informed Japan's Defense Ministry that F/A-18 fighter aircraft belonging to the Marines' Air Station Iwakuni in Yamaguchi Prefecture, western Japan, conducted such a drill on Wednesday over neighboring Hiroshima Prefecture, which prompted local residents to complain about flares generated during the drill.