A young woman lied her way into a Bronx apartment and sexually assaulted an elderly woman after Christmas, police said today.

The suspect, described as a woman in her 30s, knocked on the door of the 81-year-old victim's apartment at about 10:45 p.m. on Friday and said she was there from a hospital, police said.

The victim assumed she was there to take care of her husband. But instead, the suspect touched her groin and breast before walking out, police said.

Police are searching for the woman, who is about 5-feet-6-inches and 135 pounds.