The U.S. Air Force resumed drills involving its F-15 fighter jets Thursday following a crash earlier in the week involving one of the aircraft in waters off Okinawa.
The 18th Wing of the U.S. Kadena Air Base said in a statement that it had completed safety checks of all F-15s at the base after suspending drills following the accident.
The base set up an interim safety investigation board to look into the incident and started gathering information, it said.
"The safety of our base population and our surrounding communities remains our top priority, while we meet our bilateral obligations," U.S. Air Force Col. Brian McDaniel said in the statement.
"It is very regrettable because (restarting the drills) heightens the fears of Okinawa residents," Gov. Hirokazu Nakaima said in a statement.
An F-15 crashed into the Pacific Ocean east of the main island of Okinawa in southern Japan during a training flight Tuesday morning, but the pilot ejected safely.