A bureau de change owner has been found guilty of helping launder money for a £61m cannabis ring based in Kingston and Sutton.

After five days of deliberations, on Thursday afternoon the jury at Southwark Crown Court returned a guilty verdict by 11 to 1 against Asim Bashir, 35, of The Drive, Ilford.

During his trial, detectives showed surveillance footage of 23 visits by drug dealers, including Liam Salter who travelled from Worcester Park station, carrying holdalls filled with "hundreds of thousands pounds worth of dirty money".

It was never claimed that Bashir was a drug dealer or that all the money he transferred was drugs money.

But they said that the money couldn't have gone into his businesses without him knowing about it.

At the outset of the trial prosecutors said that in 2008 receipts for cash showed £3.5m but £9.9m was banked. In 2007 there were receipts for £4.8m and just under £13.3m banked.

Bashir insisted he had been duped by the drug dealers, who he said gave him false names, into transferring what he thought was legitimate money abroad to Pakistan and Dubai.

He will be sentenced with eight men including Mark Kinnimont, 39, of Claremont Road, Surbiton, Terrence Bowler, 37, of St Albans Road, Kingston, and Peter Brown, 37, of Kings Henry’s Road, Kingston, who have already pleaded guilty to being involved in the drugs ring.

Timothy Sullivan, 38, who gave the court a home address in Ash Court, Epsom, but was extradited from a prison in France had also pleaded guilty.

The gang imported cannabis from Holland, storing drugs and money in lock-ups and homes in Kingston and Sutton.

Detectives believe it is Britain's biggest ever cannabis haul.