Dempsey, 33, from Essex, was arrested during a raid on a property in Benahavis, Marbella for allegedly conspiring to supply 299 kilos of cocaine in spring 2009.
It follows Dempsey’s appearance on the wanted list, issued by the Serious Organised Crime Agency (SOCA) in February.
Dave Cording, of Crimestoppers, said: “This is another great result which means that now 50% of the most recent batch of wanted individuals have been arrested.
“Not only is the campaign successful in tracking people down in Spain, but it displaces them as well.”