Despite interference from protesters, divers on Friday began a preliminary survey of waters off the U.S. Marine Corps' Camp Schwab in Nago that the government needs to relocate a U.S. Marine Corps facility in Okinawa.

Divers from the Defense Facilities Administration Agency's Naha bureau, assisted by the Maritime Self-Defense Force, placed devices in the area where a replacement facility is to be built.

Japan Coast Guard boats were patrolling the area as the work began around 7:30 a.m. to prevent the protesters from impeding the divers. The process of setting up the devices is expected to take three to four days.