In 1966, land near the town of Palomares was contaminated with plutonium-239 after a US B-52 bomber with thermonuclear bombs on board collided with a KC-135 tanker aircraft. As a result of the plane crash, seven people were killed and four thermonuclear bombs were lost.
The Spanish government reminded the US of a political commitment that Madrid and Washington had signed in October 2015 on the removal of the contaminated soil to the Nevada desert, the report noted.
So far, a total of 50,000 cubic meters of contaminated soil has been scattered across several plots of land covering about 40 hectares (98,8 acres), which were fenced off in 2007 due to high levels of radiation, the report added.
During the Cold War, the US Air Force had been carrying out Operation Chrome Dome. It included the continuous presence in the air of strategic bombers with nuclear weapons, which were ready to strike predetermined targets on the territory of the USSR. However, the accident in Spain caused a serious diplomatic crisis and led to the cessation of US nuclear bombers' flights over Europe and the Mediterranean. However, such flights were finally stopped only in 1968 when another nuclear accident occurred over the Thule base in Greenland.