D.C. police are attempting to find a man who has exposed himself to children and women at least seven times since April in Northwest Washington.

But they don't have much to go on: Victims haven't gotten a clear look at the man's face, although they have told investigators that he has a potbelly and a hairy chest.

Adding to the mystery, the man has exposed himself to women and young girls from the same window of a vacant rowhouse apartment on Connecticut Avenue NW. The apartment's owner has told investigators that he does not know how the man is getting into the place, police said.

Although no one has been physically hurt, Cmdr. Jeffrey Moore of the 2nd District said, police are taking the investigation seriously.

"There is concern because this may be a gateway crime," said Moore, who has taken part in one of many stakeouts to catch the offender. "He may spiral out and move into contacting" victims.

Police have become so concerned about the man that they have taken some of the younger victims to specialists to help question them, Moore said. Those sessions have helped narrow down the description of the man, described by police as being in his 30s or 40s and having a hairy body.

The reported exposures began April 2 at 47th and Chesapeake streets NW, police said.

A 12-year-old girl was walking north on 47th Street when she spotted a man driving a maroon vehicle next to her about 4:15 p.m. The man's face was hidden by a sun visor as he raised himself off the seat to expose himself, police said.

About 45 minutes later, in the 4800 block of Albemarle Street NW, police said, a 15-year-old boy told police that a maroon-colored vehicle -- described as possibly being a station wagon with wood paneling -- slowed next to him.

The driver rose from the seat and exposed himself, police said.

On May 7, a young girl was walking in the 5200 block of Connecticut Avenue when she heard a knock on the window from inside an apartment and saw a man exposing himself, police said, and on May 21, in the 4100 block of Connecticut Avenue, police said, a similar situation occurred involving a 13-year-old girl.

A half-hour later, another 13-year-old girl reported seeing a man doing the same thing, police said.

The next day, a 12-year-old girl was walking down that same stretch of Connecticut Avenue when she spotted a man exposing himself in a window, slightly obstructed by blinds or curtains, police said.

The last reported exposure came on July 5, in that same block, when a 36-year-old woman reported seeing a man performing an obscene act inside the same apartment window, police said.

The victim told investigators that the man had exposed himself from that window in March.

Moore and other police officials said investigators have canvassed the area and questioned residents about seeing anything suspicious. Moore urged anyone with information about the case to call Officer Joe Crespo at 202-282-0043.