Two 16-year-old girls from London were arrested in Ghana after being discovered with an estimated 300,000 pounds' worth (443,000 euros, 610,000 dollars) of cocaine, customs officials said Thursday.

Her Majesty's Revenue and Customs said in a statement that the teenagers, both college students, were detained at Accra Airport by Ghanaian Narcotic Control Board officers working on a joint British-Ghanaian project targeting drug smugglers.

The head of the Operation Westbridge project, British customs officer Tony Walker, said: "The use of such young girls as couriers vividly illustrates the ruthlessness of the criminal drug gangs involved in this traffic.

"The dedication of UK and Ghanaian drug detection officers has prevented deadly Class A drugs from entering the UK."

The girls had been in the process of boarding a British Airways flight to London and were allegedly in possession of 6.5 kilos (14 pounds) of cocaine, HMRC said.

A Foreign Office spokeswoman in London said British embassy officials had been called to support the girls.

"We are aware of the arrest of two British national minors on July 2 at Accra airport," a spokeswoman said.

"Next of kin have been informed and we are providing full consular assistance. We are unable to confirm any personal details due to their age."

Operation Westbridge was launched in November 2006 to curb a rise in cocaine smuggling from Ghana.

Britain provides technical and operational expertise to counterparts in Ghana, including training and use of scanning equipment.

The United Nations Office of Drugs and Crime Annual Drug Report 2006 identified West Africa as a key staging post for drugs mules coming to Britain.