A Ground Self-Defense Force helicopter with 10 personnel aboard went missing in waters off Okinawa Prefecture on Thursday, and what could be parts of the chopper were found in the sea during search efforts.

The UH-60JA multipurpose helicopter is believed to have been caught up in an accident, Gen. Yasunori Morishita, chief of staff of the GSDF, told a news conference, as rescue efforts continued for the pilots, mechanics and other members of the Self-Defense Forces.

The helicopter disappeared from radar around 3:55 p.m. near Okinawa Prefecture's Miyako Island, shortly after taking off from there for surveillance activities, according to the GSDF.