RETURNING troops are today facing stringent security checks at RAF Brize Norton following reports the base is being used to traffick heroin from Afghanistan.

Military police have launched an investigation amid claims British and Canadian personnel are bringing drugs through the base, near Carterton, when they return from service.

The Ministry of Defence called the reports “unsubstantiated” but confirmed it had increased security. It apologised to personnel for the inconvenience.

An inquiry has been launched by defence chiefs and is focusing on service personnel at airports in Camp Bastion and Kandahar.

RAF Brize Norton — which last month underwent a £186,000 revamp — is used by thousands of troops last year as they return to Britain.

An MOD spokesman warned of the consequences for any soldiers who might be involved in drug-smuggling.

He said: “We are aware of these allegations.

“Although they are unsubstantiated, we take any such reports very seriously and we have already tightened our existing procedures both in Afghanistan and in the UK, including through increasing the use of trained sniffer dogs.

"We regret any inconvenience this causes to our service personnel.”

Officials estimate 15,000 servicemen and women pass through RAF Brize Norton’s air passenger terminal every month.

Last year, the base ferried more than 267,000 passengers to locations as such as Afghanistan, the USA, the Middle East, Africa and the Falkland Islands.

All returning personnel are now being subjected to increased use of sniffer dogs, body and luggage searches, and covert monitoring.

Afghanistan is the source of 90 per cent of the world’s opium.

Some drug bosses in the war-ravaged country have implicated soldiers in the trade.

Last year the Sunday Times spoke to one dealer who said members of the military were the second largest buyers of heroin after foreign drug lords.

The newspaper was told: “The soldiers whose term of duty is about to finish, they give an order to our boss.”

The dealer, named only as Aziz, added: “They are carrying these drugs in the military airlines and they can’t be reached because they are military. They can take it to the USA or England.”

RAF Brize Norton is the UK’s largest RAF station, employing about 3,900 service personnel and more than 600 civilians.