A DRUGS dealer was last night starting a ten-year jail sentence for the distribution of cocaine with an estimated street value of £518,000.

David Cairns was on licence from an eight-year sentence for drug supply offences when he was arrested following a surveillance operation at his remote farmhouse.

An officer hid in bushes at Pesspool Hall Farm, Haswell, near Peterlee, east Durham, and watched as Cairns rode an off-road motorbike along paths and disused railway lines to deliver half a kilogram of cocaine worth £155,000 to Paul Barker at the Grey Horse pub, South Hetton, early one April morning last year.

Mark Giuliani, prosecuting, said the police investigation began after they stopped a speeding Ford Transit van on the A19 two months earlier and found 803 grams of the drug, worth £363,000, that had been collected from Liverpool and was destined for Cairns.

Mr Giuliani said both hauls were extremely pure, indicating it had just arrived in the country.

In 2003, Cairns was jailed for conspiracy to supply cannabis, cocaine and ecstasy through an operation based in a quarry.

Cairns, 32, now of Bruce Glazier Terrace, Shotton Colliery, admitted being concerned in the supply of cocaine last year at a previous Durham Crown Court hearing.

Mr Giuliani said he pleaded guilty on the basis that he was not the main dealer, but an “intermediary for a wage’’, and had been threatened that his daughter would be killed or injured if he did not take part as he was in debt for £70,000-worth of drugs seized from his previous operation.

Osama Daneshar, mitigating, said: “The threats were effective enough for him to become involved in this offending.”

The court was told that couriers Stephen Holland, 53, of Beecham Crescent, Denton Burn, Newcastle, and Michael Branson, 38, of Tyne View, Hebburn, and Paul Barker, 46, of School Avenue, West Rainton, who was more involved in distribution, were jailed for between two and four years at previous hearings.

Judge Christopher Prince commended two officers, one of whom showed “conspicuous bravery’’ in the surveillance operation, because he could have been attacked if discovered.

Afterwards Detective Inspector Jim Tray said: “David Cairns is, in my opinion, the main organiser of a multi-million pound drugs network that has been delivering large amounts of cocaine to County Durham and Tyneside.’’