The government will ask the U.S. military to avoid flying over schools in Okinawa Prefecture after a window that fell off one of its choppers almost hit students at an elementary school earlier in the week, Chief Cabinet Secretary Yoshihide Suga said.

Suga, who doubles as minister in charge of easing Okinawa’s base-hosting woes, mentioned the plan at a meeting Friday with Okinawa Gov. Takeshi Onaga, who lodged a protest over Wednesday’s incident.

The roughly 90-sq.-cm, 7.7-kg helicopter window belonged to a CH-53E transport. It landed just a dozen meters from students at a school near U.S. Marine Corps Air Station Futenma in Ginowan.

Although no one was injured, the incident reignited safety concerns in Okinawa, which hosts the bulk of U.S. military forces in Japan.

“As for (our request to change) the flight route, I believe (Suga) said he ‘wants to realize’ rather than ‘will do his best,’ ” Onaga told reporters after the meeting, which was also attended by Ginowan Mayor Atsushi Sakima.

The request was originally made by Etsuko Kyan, principal of Futenma No. 2 Elementary School, where the window landed.

Suga promised that he would urge the U.S. to “thoroughly” investigate the cause of the incident and take preventive measures, Onaga said.

The CH-53E is stationed at the unpopular Futenma base, which is siated in a densely populated part of Ginowan.

Although the Japanese and U.S. governments have agreed on three flight routes around the base, the Okinawa Prefectural Government claims U.S. aircraft routinely fly outside of them, including over the school.

Criticizing repeated accidents involving the U.S. military, Onaga also called for Suga to reduce the burden on Okinawa associated with hosting the Futenma base.

Earlier Friday, the Ginowan city assembly unanimously adopted a resolution and a written statement urging the U.S. military to apologize to the schoolchildren and look into the cause of the incident.