Munition Support Squadrons (MUNS) are NATO units that receive, store, maintain and keep custody and control of nuclear weapons in Europe. Usually consisting of 125 to 150 troops, each MUNS is located on a NATO base that also hosts a NATO strike wing. When directed, a MUNS releases nuclear weapons to the strike wing commander.
Most details about NATO's nuclear deployments are secret. The only officially acknowledged information is that the standoff (air-dropped) weapons are currently B61 types managed through the Weapons Storage and Security System (WS3). Built in the 1980s, WS3 are vaults that con house four weapons in the floors of the aircraft shelters, making them less vulnerable to attack and more convenient for the strike commander. In 1986, the Pentagon released a list of airbases in Europe and in the Far East that have WS3s.
Since the collapse of the Soviet Union and the Warsaw Pact, the number of NATO airbases and the number of operational WS3 has been reduced. In 2017, Hans M. Kristensen, the director of the Nuclear Information Project with the Federation of American Scientists (FAS) in Washington declared that the numbers of NATO-assigned US nuclear weapons in Europe have not been changed since 2009 so it is supposed that they are currently still operational in Turkey, Italy, Germany, Belgium and in the Netherlands.
In March 2021, the Pentagon briefly posted a picture of the unit insignia of the 701st Munitions Support Squadron at Kleine Brogel Air Base, Belgium which depicted US and Belgian flags above an eagle clutching a B-61 weapon. The photo was removed after it drew media attention.