Montgomery County police are searching for a man suspected of raping or sexually assaulting seven women in their homes in a 1.5-square-mile area of Chevy Chase, Bethesda and Silver Spring. In several cases, police said, the man apologized to the women after the attacks.

The man apparently has been peeping through windows and then entering the women's homes -- three private houses and four first-floor condominiums -- through unlocked windows or doors, police said. He usually attacks between 12:30 and 4 a.m. while the women are sleeping, police said. He has sometimes used a pillow or a towel to muffle his victims' cries, police said. The attacks occurred between July and Nov. 5, police said.

"We have not had one incident where he's forced his way in at all," said Detective Richard Fallin of the Silver Spring District. "It's one of those situations, I think, where you have a peeper peeping until one day he realizes the window is unlocked and he can get in . . . . If he knows them at all, he knows them from peeping."

The man rarely talks during the attack but has threatened some of the women with a knife, police said. Afterwards, he is polite and apologetic.

"He's told several of them he was sorry. He told one woman, 'I'm sorry I had to do it this way,' " said Sgt. Harry Geehreng, a police spokesman.

According to police, all the attacks have occurred in the area bounded by Connecticut Avenue, 16th Street, the District line and Jones Bridge Road. The ages of the women have ranged from 19 to 61, with most in their late twenties and thirties.

The same man is being sought in an attack of a woman walking on Connecticut Avenue in July, police said. The victim's description of the man fits the other seven women's description, they said.