A BOGUS water worker struck twice within minutes at homes in Newsome.
The well-built conman first called at a flat on Close Hill Lane at 4.45pm on Wednesday and told the 72-year-old man who lives there that he needed to check the water.
He was allowed in and went to the bathroom and said the water was OK.
He then asked the victim to make him a cup of tea, which he did.
But the victim disturbed the intruder in a bedroom.
The bogus official claimed he had to go and see someone at nearby Croftlands and left.
Nothing is thought to have been stolen.
But minutes later he called at the home of an 83-year-old woman in Croftlands.
Again he claimed he was there to test the water and she let him in. He stole a purse before leaving.
Pc Dave McSweeney, of Huddersfield police, said: "Don't let strangers into your home, it's as simple as that. Yorkshire Water officials do not need to come in to check your water like this.
"People who work for the main gas, electricity and water companies will have proper identification badges and will be happy to wait outside while you phone up their headquarters to check they are who they say they are."
The thief who struck in Newsome is white, in his early to mid-30s, 5ft 8ins tall and thick set with a fat face and short, dark, straight hair.
He wore a dark blue jumper with a white badge and dark writing on it.
Pc McSweeney added: "This man may have tried to con his way into other homes and we need to hear from anyone who was approached by him."
Contact Huddersfield police on 01484 436664.