The Mildenhall Royal Air Force base said security staff locked down the base, used by the United States to refuel US and NATO aircraft in Europe, at about 1300 GMT following reports of a disturbance.
"Shots were fired by American service personnel and a man has been detained with cuts and bruises and taken into custody," Suffolk Police said. "No other people have been injured as a result of the incident."
The US Air Force said the incident had been contained and that the suspect had been apprehended. Police said they remained on the base. The US embassy declined immediate comment.
The 1,162-acre base, which houses about 3,100 U.S. military and an additional 3,000 family members, is set for closure after the US said it was going to move is operations from the base to Germany.
A statement for the base said the lockdown had later been lifted.
(Reporting By Andrew MacAskill and Kate Holton; additional reporting by Phil Stewart in Washington; editing by Guy Faulconbridge)
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)
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