DUBLIN gangland is reeling after the murder in Spain of one of its most vicious leaders and the attempted assassination -- the fifth in the past few years -- of career criminal Martin "The Viper" Foley.The Spanish murder in Estepona on the Costa del Sol of Paddy Doyle ended the vicious career of a criminal who, although aged only 27, was regarded by Gardai (Irish police) as one of the most ruthless and dangerous of Dublin's gang bosses.He was leader of one of two gangs based in the Crumlin/Drimnagh area of the city and who were involved in a feud which cost 10 other lives since 2001.Doyle, suspected of direct involvement in up to four murders, fled to Spain from where, according to detectives, he continued to operate a lucrative illicit drugs -smuggling operation.He was gunned down on Monday while a passenger in a jeep driven by another Dubliner Gary Hutch, a nephew of reformed robber Gerry Hutch, widely known as The Monk. Gary Hutch, a jewelry thief who served time in jail, was injured in the attack. Another Dublin criminal, "Fat" Freddie Thompson, a back seat passenger, escaped unhurt.Thompson was charged in the Netherlands in 2006 with possession of cocaine valued at almost $840,000 and six handguns. However, he was never convicted.Hutch and Thompson, both also aged 27, disappeared after the attack and were being sought by Spanish police.Detectives have not ruled out revenge by Dublin rivals as a motive for the attack on Doyle, who was shot twice in the head by a gunman firing from another vehicle. But the cops reckon it's just as likely he was the victim of foreign criminals based in Spain and whom he may have crossed.Spanish police are investigating possible links between a massive seizure of 290 pounds of cocaine in Malaga 80 miles away and the murder of Doyle on the same day.Eleven people were arrested in the operation which led to the drugs seizure, and Gardai are examining whether at least one of them had an Irish passport.It was reported locally that an Irishman and six Britons were among those detained after the discovery of the cocaine.British police believe the drugs came from Colombia and were due for distribution by drug gangs throughout Europe.Meanwhile, in Dublin "The Viper" Foley, was still recovering in hospital from gunshot wounds to the face and upper body in an attack outside a gym on Saturday, January 26. The 55-year-old, who survived four previous shooting attempts on his life, is believed to have been a victim of the Crumlin/Drimnagh gang feud.He has more than 40 convictions, some for assault, robbery and possession of threatening weapons.