Nicholas Evans, prosecuting, said: "This case involves an organised criminal network operating between the UK and Thailand. "It is alleged that teenagers were trafficked to Thailand to act as drug couriers." A fourth person, Ffion Bowes-Cavanagh Hooley, 24, of Caerau, has been charged with conspiring to evade a prohibition on the importation of a Class B drug and concealing criminal property. A spokesman for South Wales Police said: "The children remain in custody in Thailand where they are being supported by their families and the Foreign and Commonwealth Office. In June, South Wales Police was made aware that two 17-year-olds from Cardiff had been arrested in Thailand.