Detectives today warned householders to be on their guard after a pensioner was left robbed, bruised and locked in his own home by a bogus caller.

The 71-year-old man had allowed a rogue caller into his house, in Croscombe Walk, near Manchester Road, Bradford, after claiming he had come to 'check the water pipes' on Tuesday.

Detective Inspector Chris Binns, of Bradford South CID, said: "After having a look around, the man then said some pigeon droppings needed clearing and asked for £10 to do it."

The homeowner and his elderly wife handed over the cash and the caller left without doing the job.

"But he returned at around 11am the next day under the pretext of doing the work and was once again allowed into the house," said Det Insp Binns.

While inside, the intruder spotted some money on a table and went to steal it.

Det Insp Binns said that, when he realised what was going on, the pensioner confronted the intruder. He added: "A struggle followed in which the man received some bruising to his head and body."

The intruder fled from the house with a small amount of cash, first meeting an accomplice who had been waiting by the doorstep.

"On the way out, he took a key which was in the front door and locked it from the outside, trapping the couple inside."

The stunned pair called the police, who freed them within minutes.

"Once again, we would warn people not to allow uninvited guests into their home," said Det Insp Binns. "This was a really nasty incident."

He said the pair struck between 9am and noon on Tuesday and 11am on Wednesday. The first man is described as white, around 25 years old, 5 ft 8 ins tall and of medium build. He was wearing a white hard hat and a short white jacket. The man outside was Asian and in his 20s.

Call (01274) 376459 if you can help.