At St John’s airport in Antigua, visitors walk across the tarmac to a tiny salmon-pink terminal where a steel band and a cup of rum punch greet them before they reach the immigration desk.

Ramshackle houses and green hills overlooking a turquoise sea reinforce the tourist fantasy of sun, sand and safety. But last week the idyll collided with the darker reality for residents of Antigua and other Caribbean islands when Catherine and Benjamin Mullany, both 31, were shot as dawn rose over their honeymoon bungalow.

Catherine was killed instantly; Benjamin arrived home in Britain yesterday via air ambulance with a bullet in his head and a broken leg. Doctors in Antigua said they believed he was brain dead but Cynlais and Marilyn Mullany, his parents, are thought to want a second opinion from British medics.

The brutality of the crime, and the fact that the victims were a photogenic young British couple, focused attention on what locals have long known but the tourist industry has preferred to cover up.

Violent crime and the gun culture that accompanies it are spiralling out of control – not just in Antigua and Barbuda, a tiny nation of 176 square miles, but right across the Caribbean.

The Mullanys were married on July 12 at St John the Evangelist church in Cilybebyll, a hamlet near Swansea in south Wales. Catherine had recently qualified as a paediatrician. Benjamin was a physiotherapy student.

Antigua, where they chose to spend their honeymoon, has a reputation as one of the Caribbean’s safest and most welcoming islands – unlike Jamaica, which is notorious (some say unfairly) for violence.

The island has a scruffy charm and an old-fashioned atmosphere; tiny churches are full on Sundays and scrubbed boys and girls in immaculate uniforms stand at bus stops on school days. Until recently few locked their doors and islanders routinely walked home in the early hours of the morning from the numerous dance clubs.

Behind this allure, however, Antigua is suffering a plague of violence. Every April it hosts Race Week, a sailing regatta that draws yachts from around the world. Residents set up stalls in English Harbour, cooking local specialities such as jerk chicken as sailors down rum punch. This year, for the first time, armed soldiers mingled with the dockside crowds.

One of the main reasons for the escalation in violence, according to residents and police sources, is the enforced return of emigrant criminals.

“Each year the United States, the United Kingdom and Canada deport thousands of people convicted of various crimes to their countries of citizenship in the Caribbean. There is a widely held belief in the Caribbean that recent crime troubles can be tied directly to the activities of deportees who have learnt criminal behaviour in the developed countries,” said a report issued last year by the United Nations Office on Drugs and Crime and the Latin America and Caribbean region of the World Bank.

The Antiguan government says almost 300 have been returned to the island in the past 10 years. A few were from Britain, but the majority came from the United States.

“They are sending back these violent guys. Some left here as babies; they come back as criminals after their graduation from American prison,” said Andy Liburd, editor of the Antigua Sun newspaper.

“These people don’t know anyone; they don’t know our culture. Most don’t have family here or if they do, say, have an aunt here she doesn’t want to take them in because of their criminality. Crime is entirely out of control.”

Antiguans said the deportees had also brought a change in drug habits; instead of smoking marijuana, users are turning to cocaine and crack. Aggressive youth gangs were another new threat. “The police don’t have guns,” said Liburd. “Times are changing. Gone are the days that a truncheon will turn off a criminal.”

Ramesh Deosaran, professor of criminology at the University of Trinidad and Tobago, added: “In the past 10 years across the Caribbean the rate of the serious crimes of drugs, kidnappings and murder has risen dramatically. Coupled with that, more recently there has been an acceleration in the violence and randomness of crime.”

The area has become a staging post for drug smugglers. As US-led efforts curtailed the flow of drugs out of Central America, traffickers have turned to the Caribbean as a transit point. Last year’s UN/World Bank report on the region spoke of a “torrent of narcotics with a street value that exceeds the value of the entire legal economy”.

It added: “Murder rates in the Caribbean – at 30 per 100,000 population annually – are higher than for any other region of the world and have risen in recent years for many of the region’s countries.”

For nearly two weeks none of this impinged on the Mullanys’ honeymoon at the boutique Cocos hotel. Last Saturday, on the final evening of their holiday, they dined on a veranda before retiring to their pastel green bungalow perched on a hill above the sea.

Police believe the couple were sleeping when at least two intruders broke in. Theirs was the first bungalow the killers would have encountered at the top of a dirt track that leads up from a road on the inland side of the hill. The back door to the bungalow’s kitchen was forced open.

It appears the Mullanys got up before they were shot. Guests in neighbouring bungalows heard screams and gunfire at about 4.40am. Most went back to sleep, thinking it was part of the carnival celebrations held on the island last week, but one alerted the hotel’s security guards, who called the emergency services at 5.17am. A guest who is a nurse gave aid until the ambulance arrived.

“When we walked into the room I got the shock of my life,” said a paramedic, who did not want her name used.

“Mrs Mullany was lying on the floor on her back at the foot of the bed. She was dressed in night clothes – a vest and loose trousers. I could see she was dead.”

Catherine had been shot at close range in the forehead. Benjamin had been hit in the back of the neck by a bullet that pierced his brain. The paramedic said he was still alive, moving his hand and murmuring something. “Mr Mullany was on top of the bed, wearing just briefs,” she said. “There was so much blood around his head. The mosquito net around the bed was soaked red.” He was in a coma by the time the ambulance reached the hospital.

The security guards who were supposed to have been patrolling the grounds were questioned by police and released.

Catherine Mullany was the 10th murder victim in Antigua this year. Nineteen people were killed in 2007, three times Antigua’s annual rate five years ago. The police force is undermanned and underequipped. Some experts say their poor pay has made them susceptible to being paid off to ignore crimes, or being too unmotivated to pursue them.

The Antiguan government has brought in a new police commissioner, Gary Nelson, a retired officer from Ottowa, and three of his colleagues from the Canadian mounted police to combat the problem. Nelson says he needs to beef up his 350-man force by at least 200.

The commissioner last week accused his force of “turning a blind eye” to crime and said he had asked Scotland Yard and the FBI to help with the murder investigation, since the island had only one forensic expert. London confirmed yesterday that British detectives were on their way.

Baldwin Spencer, the Antiguan prime minister, has vowed to improve security. “Those criminal deportees with skills developed in the US and UK are impacting tremendously on our society,” he said in an address to the nation last week.

Antiguans are frightened by the change. Dana Nicholson, whose father was a founder of Antigua Race Week, recalled her grandfather’s story that when he accidentally left his life savings in a bag at the butcher’s, a man rode up on a donkey to return the money.

That atmosphere has been poisoned. “We were sitting down to dinner recently and there was a commotion on the street outside,” said Nicholson. “A woman had been hit in the head with the butt of a gun. She recognised her attacker as the son of a local deportee from America, but the police never acted, even though they knew who he was.”

She said that Antiguans did not know how to cope with the extreme violence of those who are essentially foreigners: “We’d never seen such ‘bad-mindedness’. It’s beyond control. It’s our home, but we feel like moving away.”

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