Patricia Cahill, 17, and Karen Smith, 18, were stopped by customs officials at Bangkok airport trying to board a flight to Amsterdam.

They found nearly 70lb (32kg) of powdered heroin with a street value of about £4m hidden in shampoo bottles and coffee and biscuit tins.

The girls claim they did not know what was in the containers, given to them by a third person.

They are denying the allegations being made against them.

Thai justice

The British consulate in Bangkok has appointed a solicitor to represent Ms Cahill and Ms Smith in the Thai courts.

Drug trafficking is punishable by death in Thailand but foreigners usually have this sentence commuted.

Under Thai law Ms Cahill is too young to be executed.

Speaking from his home in Birmingham Ms Cahill's father did not even know his daughter had left the country. Patrick Cahill thought she was holidaying in Scotland.

He said that Patricia was "dead against drugs, she was dead against abortions and things like that."

The poppy fields of the so-called 'Golden Triangle' - between Thailand, Laos and Burma - have attracted drug smugglers since the 1960s.

Thailand has responded to international pressure to control the illicit trade by enforcing harsh sentences and searching all baggage leaving the country.

Ten years ago British nurse Ruth Nightengale served 18 months of a 20 year sentence for heroin smuggling in Thailand before her release after receiving a royal pardon.

	E-mail this story to a friend