United States Air Force officials said a four-month investigation at RAF Lakenheath had "provided evidence" the men might have been involved in the "use, possession, and distribution" of drugs including ecstasy and marijuana.

Lakenheath is home to about 5,000 servicemen and women, making it the largest US airbase in Europe.

None of the 27 involved has been charged, and all are continuing to work at the base.

Lakenheath is the largest US airbase in Europe

The head of public affairs for the base, Major Francisco Hamm, said the investigation had not been completed.

It was possible the inquiry, by the Ministry of Defence Police and US security forces, could end in military court proceedings, he said.

Those under investigation are aged between 17 and 30, and range in rank from airman to staff sergeant.

Some of the men are assigned to the 439rd fighter squadron.

Servicemen from a further five squadrons are among those being investigated.

Major Hamm said the USAF operated a zero tolerance drugs policy and servicemen and women were regularly tested.

Crews from Lakenheath have been involved in recent years in strikes against Libya in the mid-80s, the Gulf Conflict in 1991, attacks on Serbia in 1999 and in Afghanistan last year.