US Air Force investigators are looking into alleged drug use of 10 officers at six bases in the US and Britain, including RAF Lakenheath.

Nine lieutenants and one captain are being investigated for illegal possession of recreational drugs, according to USAF spokesman Lt Col Brett Ashworth.

The investigation has spread since beginning with two officers at Edwards Air Base in California after the airmen were found to have contacts with others about drug possession, said Lt Col Ashworth.

Lt Col Ashworth confirmed that the probe now includes RAF Lakenheath, as well as Malmstrom Air Base in Montana, Schriever Air Force Base in Colorado and Vandenberg Air Force Base in California.

No other details are being released about the investigation, which is being conducted by the Air Force Office of Special Investigations.