About 150 residents of the Twinbrook area of Rockville, where a nighttime burglar has struck about 25 times since early September, met last night to scold their police chief and learn how to burglarproof their homes.

"This is an after-the-fact meeting that should have been held three weeks ago," one woman shouted from the packed audience at Rockville United Church. "I had to find out about burglaries on my street by reading it in the newspapers," another woman said.

Rockville Police Chief Jared D. Stout conceded that "we simply dropped the ball on this one" and agreed that the citizens should have been given more information about the thefts. He said there had been a "breakdown in communications" between himself and officers who patrol the neighborhood.

The chief did bring some good news. He said that although no arrest has been made, a suspect has been questioned, and "in the six or seven days we've been talking to him, burglaries in the area have ceased."

In the past two months, a man who dresses in black has stolen purses, wallets and other valuables from the homes of Twinbrook residents.

The burglaries, which police believe is the work of one person, have primarily been committed in a 100-block area surrounding the Twinbrook Shopping Center, usually between midnight and 6 a.m. The area is popular with police officers, a number of whom live there.

The burglar has been seen twice as he dashed through houses in the dark while making off with stolen items. So far, the stolen cash and watches and televisions -- and a .25-caliber gun in one case -- amount to about $7,000.

Last night, Officer Victor Grasso presented a film on equipment and techniques residents can use to make their houses more secure against burglary. Grasso also described how residents can form "Neighborhood Watch" groups to monitor suspicious people and vehicles in their area.

One homeowner was eager to learn her legal liability if she unleashed her German shepherd attack dog on a suspected burglar found in her home.

"I frankly don't recommend deadly force," said Chief Stout, who explained that a citizen could face criminal charges if an intruder were injured or killed.