A U.S. military official apologized Monday to an elementary school in Okinawa where a CH-53E helicopter window almost fell on children last week, while the governor blasted U.S. plans to announce the resumption of flights of that type of chopper later in the day.

The official also told the school that the U.S. military had reconsidered flight rules at Marine Corps Air Station Futenma, where the chopper took off from, and confirmed it would make every effort not to overfly the school.

No one was injured when the metal-framed window landed on school property near the base last Wednesday, but the latest accident stoked local anger about the large U.S. military presence on the island.

Col. Darin Clarke, who manages the U.S. Marines’ government and external affairs in the Pacific, apologized to Futenma No. 2 Elementary School Principal Etsuko Kyan for causing great unease at the school and in the region.

Okinawa Deputy Gov. Moritake Tomikawa told reporters he was notified by U.S. forces that the resumption of CH-53E flights would be announced Monday. Sources said the government had decided not to oppose the plan.

Tomikawa said Brig. Gen. Paul Rock, commanding general of Marine Corps installations in the Pacific, told him so on Sunday.

Okinawa Gov. Takeshi Onaga called the decision “truly ridiculous,” and said it showed the central government was “incapable of being involved.” He also said the U.S. military was “not a good neighbor.”

In Tokyo, Defense Minister Itsunori Onodera said the government had not “received a sufficient explanation about (U.S.) measures to prevent a repeat” of such accidents.

U.S. officials said pilot caused the window to detach, but this explanation has not satisfied residents in Okinawa, where tensions frequently flare over the prefecture’s disproportionate share of U.S. military facilities in Japan.

Parents of children who attend the school are among those rejecting the decision to resume flights so soon.

Resident Tomoko Miyagi, who was taking her 12-year-old son to the school, called the move “unforgivable” and said it shows “contempt for the people of Okinawa.”

The window, about 90 cm square and weighing 7.7 kg, fell off a CH-53E transport helicopter flying over the school and landed only a dozen meters away from where children were exercising.