Manchester police have seized more than 50 kilos of heroin woven into hand-made rugs from Pakistan with an estimated street value of five million pounds.
Sniffer dogs alerted Border Force officers at Manchester Airport to one of the carpets containing small packages of heroin that arrived from Peshawar, Pakistan, via Abu Dhabi.
Several other carpets also tested positive for heroin in what investigators describe as a "sophisticated" operation to smuggle drugs into the UK. At 50 kilos, the haul is already one of the largest drug seizures at Manchester Airport and could be worth more than five million pounds.
Pete Avery, from the NCA's Border Policing Command, said: "It was a sophisticated concealment and demonstrates the lengths organised crime groups go to in an effort to avoid detection."
Two men, aged 35 and 51, have been arrested in connection with the Class A drug haul at a London business address on 29 April. They have been released on bail.
The arrests and the seizure took place in April, but details have only just been released to the public.
Linda Paul, assistant director for Border Force, said: "This is an extremely impressive seizure and I would like to praise the vigilance and hard work of my officers who have ensured that a substantial amount of a harmful drugs have been kept off our streets.
"At this stage it is impossible to put an exact value on the drugs because forensic tests have yet to be carried out. However, it is safe to say that we are looking at a significant amount."