The bodies of the timeshare operators Billy and Flo Robinson were discovered next to their luxury cars in Tenerife in 2005.

The gunmen lay in wait as their prey parked, before riddling the car with bullets. Two of the passengers were killed immediately; the third died later in hospital.

The dead, all Colombians, were the latest victims of gangland hits on the Costa del Sol in the past three weeks, raising fears that a new crime war has erupted in a part of Spain traditionally popular with British expatriates.

These gangsters, say experts, are not looking for a quiet life. Colombian and Eastern European, they are ready to spill blood in their ruthless pursuit of profits from the multimillion-pound cocaine trade. The resulting tit-for-tat killings mean that the days of the so-called Costa del Crime, when retired British underworld “faces” kept a low profile, are over.

Last month an Estonian man was shot in the head in The Point, a bar in Marbella that is popular with Irish immigrants. Another man’s body was found in a burnt-out car in Estepona. He has not been identified.

A source at the Spanish Serious and Organised Crime Agency said: “The Iberian Peninsula is the main route for Class A drugs like cocaine, Ecstasy and heroin into the UK. The Colombians sell Class A drugs to British criminals, who then supply it to the UK.

“The difference between the two is that British criminals use murder and threats only as a last resort. The Colombians are more ready to settle scores.”

The Central Brigade for Organised Crime estimates that between 20 and 30 Colombian gangs with at least 300 members are operating in Spain. One officer from the unit told The Times: “They are drug dealers and robbers who are based in Spain but are capable of working across Europe. They are not afraid to use violence whenever necessary.”

There are 274,000 registered British residents on the Costa del Sol, and many thousands more are thought to live there for at least part of the year. For those seeking a quieter pace of life, random shootings are deeply unsettling.

Gwilym Rhys-Jones, adviser for the Costa del Sol Action Group, which offers support and advice for British expatriates, said: “It gives a feeling of anxiety here because these shootings happen in broad daylight in places which are ‘British territory’. What is scary is the East European gangs, who have no compulsion about using violence. People are horror-stricken.”

The Russian mafia has also extended its tentacles across Spain, exploiting lax property laws and a lack of police resources to launder millions of pounds gained from arms dealing, drug smuggling and prostitution. Last year, police struck a blow against the Georgian mafia with the arrest and extradition to Spain of Zajar Kalashov at his mansion in Dubai. Nicknamed “Mr Invisible” for his ability to elude police, he is accused of ordering the murder of a judge.

British criminals have not been averse to wiping out opponents. Last year, in The Point, William Moy, 43, from London, was gunned down at close range. In the same month, the Dublin gangsters Shane Coates, 31, and Stephen Sugg, 27, and the British playboy drug smuggler Colin Nobes, 47, were also murdered. The corpses of Coates and Sugg were found in a cement pit and Nobes’s was found under a motorway bridge.

The bodies of the timeshare operators Billy and Flo Robinson were discovered next to their luxury cars in Tenerife in 2005.