He is the hard-working police pooch who has been sniffing out criminals for seven years.

But now retriever Bill has bowed out to enjoy a retirement of walks in the park, rather than following his nose to stashes of drugs and guns for Leicestershire police.

His last duty was an appearance at a Leicester college yesterday where he helped police and staff educate young people about drugs and the law.

Bill, who "joined" the force as a seven-week-old puppy is now eight years old, and is to be taken in by Pc Harvey Watson, Leicestershire's current beat bobby of the year.

Although his days with the police are at an end, Bill's urge to sniff out wrongdoers will remain as strong as ever, according to his handler, Pc Terry Durham.

Pc Durham, who is based at the dog unit at force headquarters in Enderby, said: "He came to the force at seven weeks and was on the streets when he was one.

"He had a result on his first job and he has gone on to find firearms on quite a few occasions, identified a cannabis house and led us to every kind of illegal drug going.

"He's been living with me and he's been a great companion, I'm happy he's retiring because he deserves it.

"I've worked with a few dogs down the years and I would put them all on a par with each other, but he has been very successful."

Pc Watson, beat officer for city police's campus, covering the University of Leicester, Victoria Park and Regent and Wyggeston and Queen Elizabeth I colleges, said; "I'm going to give him a good home to spend his retirement. The force likes to give the dogs a good life after they have served all that time.

"We'll be careful when we're walking him because the instinct to sniff out drugs or firearms will probably never leave him.

"He's a happy, playful dog and he'll be getting plenty of long walks."

The dog section at Leicestershire police headquarters in Enderby has a team of 20 German or Belgian Shepherds and 10 specialists such as Bill, who can sniff out drugs, firearms, explosives and cash.

Inspector Luke Russell, head of the unit, said: "People have said to me 'where do dogs fit into policing in the 21st century when we have all this technology at our disposal?' "They are absolutely essential and the bond between the dog and the handler is essential, they're a team.

"We try to retire the dogs at Bill's age because it gives them a time of being pets. He's done his work and now he's earned a rest."