Two 16-year-old British girls who were arrested in Ghana for allegedly trying to smuggle out cocaine worth £300,000 had told their parents that they were going on a school trip to France.

Yetonde Diya and Yasemin Vatansever, from Islington, North London, are said to have been promised £3,000 each by a Ghanaian man they met in London for bringing back two laptop bags.

According to Ghanaian police, the pair, who attended Islington Arts and Media School, had had all their living expenses in Ghana paid for since they arrived in the country on June 26. They were about to board a late British Airways flight home on July 2 when they were arrested and have been held in custody since.

Speaking by telephone from prison last night, Miss Vatansever claimed they had been tricked into carrying the drugs back to London. She told Channel 4 News: “There were basically two boys over here who gave us two bags, and told us [that] it was an empty bag. We never thought anything bad was inside . . . and they told us to go to the UK and drop it off to some boy . . . at the airport.

“It was basically a set-up. They didn’t tell us nothing. We are innocent. We don’t know nothing about this drugs and stuff.”

According to their police statement they were met in Accra by two young Ghanaians, Emmanuel and Kwami. Mark Ewuntomah, deputy director at the Ghanaian Narcotics Control Board, who interviewed them, said: “They were upset and are regretting what they have done. When I spoke to them they were crying.”

Officers from the narcotics control board, who have been trained by British Customs officers, saw the girls acting suspiciously at Kotoka airport in Accra and pulled them over as they were heading to the aircraft.

Their luggage was searched and 6.5kg (14lb) of cocaine was allegedly found, apparently hidden in two laptop bags that the girls had been given.

The two have appeared before a court and been provisionally charged with “attempting to export a controlled substance without a licence”. They were remanded in custody and are likely to stand trial before a juvenile court. If convicted, as minors they would serve five to ten years.

A source at the narcotics control board told The Times: “They were given free tickets to come to Ghana and promised £3,000 each for bringing back two laptops. Their hotel was paid for and all their living expenses were met. They met a Ghanaian man called Jay in London about a month ago and he set it up.”

Miss Vatansever’s sister, Shanel, 19, speaking from a mother and baby unit in London where she gave birth a few days ago, told The Times: “I had no idea she’d gone to Ghana. I’d heard she was going to France.”

She said that her sister, who was born in Britain to a family originally from northern Cyprus, wanted to be a social worker and has a place to study social work at college.

“She doesn’t smoke or drink or go out clubbing. She’s normally a sensible girl and hearing all this surprises me.” Officers from the narcotics control board in Ghana have been part of Operation Westbridge, a project set up with HM Revenue & Customs to combat smugglers using Accra airport as a gateway to Europe.

A Foreign and Commonwealth Office spokeswoman said that officers from the British Embassy have been supporting the two girls and have visited them almost daily.

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