Police in Antigua are questioning a local drifter who befriended Catherine and Ben Mullany just days before they were shot while they slept in their holiday cabin.

The man met the couple on a beach and drove them around the island in their rented car on July 20, one week before Dr Mullany was killed and Mr Mullany critically wounded in their cabin at the Cocos Hotel.

He was described by one acquaintance as a drifter, with his hair in Rastafarian-style dreadlocks, who worked on the beach approaching tourists.

Police picked him up for questioning in their initial sweep after the shootings because he had a criminal record and was out on bail, the source said, adding that he was rearrested after a tip-off that he had taken the couple on a tour of the island.

“The couple had rented a car and driven round the island with him. I think the agreement was he was offered US$85 (£43), he [demanded more and] got US$150,” the source said.

Inspector Cornelius Charles, of the Antigua police, denied that any such person was in custody.

Mr Mullany is on life support with a fractured skull and broken leg and was described by a doctor as brain-dead.

The 31-year-old physiotherapist from the village of Ystalyfera, near Swansea, is being taken back to Britain today by his parents. He was taken out of the intensive care unit of Holberton hospital on the outskirts of the Antiguan capital, St John's, on a stretcher and is being flown home in an air ambulance.

Mr Mullany and his parents — Marilyn and Cynlais — are expected to arrive in the UK tomorrow.

A post-mortem examination was conducted on Dr Mullany, from Pontardawe, South Wales, on Wednesday and her body was due to be flown home for a funeral.

The killings have prompted the Antiguan Government to increase efforts to tackle the surging crime that has claimed ten lives this year. Baldwin Spencer, the Prime Minister, announced a series of measures in a televised address on Wednesday night. He said that police would resume random stop-and-search operations to root out firearms and illegal drugs.

Mr Spencer said that the Government would install surveillance cameras in key locations and was considering the introduction of new wiretapping legislation. He pledged to ensure that violent offenders were no longer punished with just a fine. Immigration controls will be tightened and criminals deported to Antigua from Britain and other Western nations would be subjected to close monitoring.

“These extraordinary times and crimes call for extraordinary measures,” Mr Spencer said. “Our nation has always been known as a safe destination. Our very brand is based on people being safe in Antigua and Barbuda. Accordingly, your Government will not tolerate any action that will tarnish the reputation of this country.”

Antigua is struggling to cope with a Caribbean-wide surge in crime attributed to gangs, drugs, guns and the return of large numbers of Caribbean-born criminals deported from Britain, Canada and the United States. At least 12 street gangs have been identified in Antigua: the Royal Hustlers, the OT Bloods, Black Medallion, Ants Nest, Brick Wall, Thug Mansion, Royal Flock, Purple Haze, Black Juice, Frank Tug and the US-based Crips and Bloods.

Murder rates in the Caribbean — at 30 per 100,000 population annually — are higher than in any other region of the world, dwarfing Europe's murder rate of 2 per 100,000. “Wedged between the world's source of cocaine to the south and its primary consumer markets to the north, the Caribbean is the transit point for a torrent of narcotics with a street value that exceeds the value of the entire legal economy,” the UN Office on Drugs and Crime said in a report on the region last year.

Youths hanging out at the recreation field at Bolans, the village nearest to where the Mullanys were shot, said that drugs and violence were getting worse. “We need the military. We need some heavy artillery in this place,” said Elroy George, 22.

John Bailey, 15, who is known on the street as “Dipset”, said: “It's a badly terrible situation. As I am getting more mature, it's much tougher.”

Many people in the Caribbean blame returning deportees from the United States, Canada and Britain for bringing more violent tactics to their neighbourhoods.

“The main issue is that of deportation,” said Timothy Payne, a columnist and managing editor of the Antigua Sun newspaper. “A lot of these people who are being sent back do not have an idea of Antigua culture. They left when they were three years old and are coming back with new crime techniques.”

“To any small-island developing state, this figure is astronomically high. In ours, particularly, with its small population, these criminal deportees, with skills developed and nurtured in the US and UK, are impacting tremendously on our society,” Mr Spencer said during his televised address.

The UN report found no direct link between deportees and the surge in crime. Of 332 criminal deportees returned to Barbados between 1994 and 2000, 13 per cent were later charged with a criminal offence.

In Trinidad & Tobago, 15 per cent of the 565 deportees received between 1999 and 2001 got in trouble with the law again - a low recidivism rate compared with criminals released from local jails.

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