An operation to restrict smuggling has increased the number of drugs mules caught carrying cocaine, say customs officials.
Swabs of passengers at Jamaican airports can detect traces of drugs
The joint operation between UK and Jamaican authorities has focused on Gatwick, Manchester and Heathrow airports, as well as airports in Jamaica.
The number of cocaine couriers arrested in the UK has dropped by three-quarters over the past year, according to figures released on Thursday.
And more than double the number of drugs mules - known as "swallowers" because they carry the drugs in packages in their stomach - have been arrested in Jamaica before boarding flights.
The figure rose to 216 over the period from June 2002 to May 2003, customs officials said, up from 82 arrests in the previous 12 months.
New tactics include the use of x-rays and swabs at Jamaican airports which can detect minute traces of cocaine on passengers.
In one case last June, customs officers who x-rayed a young Jamaican woman who travelled to Heathrow from Kingston found she had swallowed 40 or 50 packages.
Derek Bradon, head of drugs policy implementation for HM Customs and Excise, told a conference of police chiefs in Blackpool that drugs barons were now having to send couriers from elsewhere.
And MP John Healey, Customs minister and economic secretary to the Treasury, said: "We are hitting the smugglers where it hurts - disrupting the supply of cocaine to the UK before they even get on the plane."
He said Operation Airbridge would help cut the supply of cocaine and reduce the amount of drugs-related crime in the UK.