Two Bradford sisters are battling for their father's release from an overcrowded jail in the Dominican Republic.

Precious metal trader Asaf Darr, 46, and two Dutch colleagues were arrested in November 1999 during a business trip to buy gold in neighbouring Haiti.

But they were detained on suspicion of money laundering after they were found to be carrying more than $750,000 US dollars (£535,000) when they drove back to the Dominican Republic after the deal in Haiti collapsed.

Despite being cleared of all charges in March, Mr Darr and his colleagues have been kept in jail while prosecutors appeal against their acquittals.

His daughters Sophie, 19, of Old Thornton Road, Fairweather Green and Sarah, 20, of Bushill Fold, Queensbury, pictured, have spent more than a year unsuccessfully lobbying the Foreign Office through Bradford West MP Marsha Singh to try to secure his release.

But in a reply to Mr Singh, Foreign Office Minister Baroness Scotland, QC, says although British consular staff are monitoring his case, they are unable to intervene with the legal process under international law.

Now Mr Darr's case has been taken up by the charity Fair Trials Abroad.

Speaking of their father's plight, Sophie, said: "All the Foreign Office keep saying is that they can't intervene in their legal process.

"We've written to our MP, we've written to 10 Downing Street. We've been trying to find out as much as we can.

"We can only do so much, we're just going round in circles, we're very depressed. We've been trying to get him out for the last two years and it's getting ridiculous.

"Every time we think we've had a breakthrough another few weeks will pass and we'll be back to square one."

Fair Trials Abroad director Stephen Jakobi said he was very concerned about the amount of time Mr Darr has been held.

"The position appears to be that he's been acquitted and the prosecution are appealing that.

"It's not a case where there's no evidence, it's a case for judgement. If he's shown where the money came from that should be the end of the matter. I'm very concerned this sum of money may have some effect on what's going on."

Speaking to the Telegraph & Argus on a mobile phone from Najayo Prison, Mr Darr, who was brought up in Bradford but emigrated to the US when his marriage ended, described how he and his colleagues were waved through by customs officers when they tried to declare the cash on crossing the border from Haiti to the Dominican Republic.

As they drove on in their hire car they were arrested at an army checkpoint two kilometres along the road and were searched by soldiers who confiscated the cash.

"We gave them all our papers and information and collaborated with them to the fullest. But right away they said this money was from drugs because the area is known for that kind of activity," said Mr Darr.

"The whole problem here is that the country is so corrupt that the money they seized from us, I think it's disappeared, there can't be any other reason why they're holding us here."

Mr Darr said he is held in diabolical conditions.

"The prison is meant for 700 people, there's more than 3,000 people here. I have to pay for this slab of concrete to sleep on, I even have to pay for water to drink," he said.

Mr Jakobi said he was hopeful that Fair Trials Abroad will be able to help Mr Darr.

"I'm confident that we'll get Government movement on this," he said.