While most dogs content themselves with sniffing lamp posts on their nightly walks, Sony the Labrador has his nose trained on far more important targets.

The one-year-old sniffer dog is the latest recruit to the Bradford District Drugs Team.

And Sony was using his superb sense of smell for the first time on Friday night.

Working in rotation with fellow Labradors Jackson and Ben, he was checking people entering and leaving nightspots Revolution, Livingstones, Walkabout and the Queens Hall.

Sony stood happily wagging his tail in the club foyer. If he detected any illegal substances, he would sit down, subtly alerting handler PC Chris Glassett that the person might be carrying drugs.

The dogs worked in short bursts, swapping places every ten minutes or so to give their sensitive noses a rest.

Partygoers queuing to get into Walkabout said it was a great way of targeting drug users. Jane Reynolds, of Shelf, said: "Drugs are not a problem in these pubs, but I think you feel safer when you see the police around."

Sarah Bevan, who was visiting family in Bradford from London, said sniffer dogs are a familiar sight in the capital.

"When you get off the trains you see the police dogs - it's quite normal," she said.

"People talk about it compromising their civil liberties, but I don't think it impinges on that. If you take drugs in a public place you have to accept that you may be caught."

Richard Williams, of Oxenhope, said: "It's important to make it feel safer for people who come to clubs. And as a parent as well, I think it's a really positive move."

PC Mark Walker, who helped to train the dogs, said he was pleased with the way they coped on their first night out. "You have to realise the dogs are very young and it's only their first exercise, but so far they are working really well," he said.

Anyone suspected of carrying drugs would be searched in special vans and arrested if drugs were found. They would be given the opportunity to talk to specialist counsellors in the cells who could offer help and advice about drug abuse.

By the end of the dogs' first shift, officers had searched three people and arrested one for the possession of cannabis.

Gavin Richards, of Livingstones, said licensees in the West End were strongly opposed to drug use and welcomed the chance to push the message that they would not tolerate drugs. "We are fully behind this latest campaign which will help to make Bradford pubs and nightclubs a safer place to be," he said.

Chief Superintendent Graham Sunderland, speaking on behalf of Bradford's three divisional commanders, said this was another weapon to keep up the pressure on drug dealers.