The Palomares accident occurred on 17 January 1966, when a United States Air Force B-52G bomber collided with a KC-135 tanker during mid-air refueling at 31,000 feet (9,450 m) over the Mediterranean Sea, near the Spanish village of Palomares in Almería province. The collision destroyed the tanker, killing all four crew members, and caused the bomber to break apart, resulting in the deaths of three of its seven crew members. The B-52G was participating in Operation Chrome Dome, a Cold War airborne alert mission involving continuous flights of nuclear-armed bombers.