SAN DIEGO -- San Diego city officials are warning the public of a man who dresses up as a city worker to steal items from people's homes, 10News reported.

According to the San Diego Police Department, the man has stolen items from two senior citizens -- one in the Rolando area and, four days later, an 87-year-old woman in Oak Park.

Curt Kidman of San Diego Public Utilities said a man posing as a San Diego Water Department employee knocks on the door of his victims, identifies himself as a water department worker and tells the victim that he needs to check the water pressure in the house.

Once inside, he asks the victim to flush the toilets while he runs water in the kitchen, police said.

As the victim follows his directions, police said the imposter scours the house for valuables.

The Oak Park woman told 10News she was shoved to the ground during the robbery.

"If they do show up on your door, ask for ID. Check to see if they have any kind of uniform on. Look outside to see if they are in a truck," said Kidman.

Police said the imposter in the Rolando case went to one of the homes, showed and ID and was in uniform.

The man in the Rolando case was described as white, about 50 years old with a raspy voice, approximately 5 feet 5 inches tall, and weighing around 160 pounds. Police said he identified himself as "Rich."

"Be aware that we really don't go in your house; you should really check," said Kidman.

Kidman also said residents can always call the city to verify the identity of the person at the door.

Police have not made any arrests in the cases, but are urging residents to contact authorities if more information is needed.

They said they believe the imposter is the same person in both cases. In 2007, there were two similar incidents, but police said they were not sure that suspect was the same person.

The city has a special Web site to help residents spot imposters at www.sandiego.gov/water/operations/imposters.shtml.