Annandale residents awoke yesterday to find their Fairfax County community blanketed with gang graffiti, and police said they will increase patrols, post "No Trespassing" signs and help organize a Neighborhood Watch program to attack the recurring problem.

Police said 23 cases of property destruction took place Monday night between 10 p.m. and midnight, affecting 14 cars, three buildings, three signs, two dumpsters and a fence.

Most of the graffiti, which was still visible yesterday, said "South Side Locos" or "SSL," a Latino gang. There was also a crossed-out "MS," which stands for the rival gang Mara Salvatrucha, the largest and most violent street gang in Northern Virginia.

Police would not disclose which gangs may be involved but said the incident was most likely a gang staking out its territory.

"I don't want to alarm the community," said Officer Bud Walker, a police spokesman. "I don't think that this is going to escalate into violence."

At least seven graffiti incidents have been reported in the Annandale area in the last month, police said. Ralph Porter, the site manager for the Briarwood Court North condominium, said he has reported at least 10 incidents since early March. Porter said he has noticed young men smoking and drinking late at night and then some vandalism just hours later.

"The police have done little or nothing," Porter said. "The police come out. They take a police report, and it's forgotten about."

But Walker said that the county has ordered increased police patrols in the area recently and that undercover officers have also been deployed.

Police are promising to do more. Capt. Jack Hurlock, Supervisor Sharon S. Bulova (D-Braddock) and two police patrol officers met yesterday with members of the Briarwood community and its management company, Jeffrey Charles & Associates.

At the meeting, police promised to increase the number of officers in the area -- both uniformed and undercover -- and help the community develop a Neighborhood Watch program, Bulova said. "No Trespassing" signs will be posted so that loiterers can be legally removed when police are called, she said.

Residents, working with police, will get a court order to ban certain individuals known for vandalism from those properties, Bulova said. In addition, the community will ask Dominion Virginia Power to brighten the streetlights in the area. Apparently, over the years, the lamps have dimmed, Bulova said.

Police are also considering creating a satellite office at Heritage Mall on Heritage Drive.

"I think it's definitely going to happen," Bulova said, but she added that it might take a few years.

Marco Lugo, 35, a member of the Briarwoods condominium committee, said he is optimistic that the county will make progress.

"Right now we've come out of this meeting with a good sense of commitment," said Lugo, adding that Briarwood was to receive a district award last night for its attractiveness. "I'm looking at the value of my house, and I don't want it to drop because of gangs."

Sergio Toro's car was spray-painted with gang symbols. Cars, buildings, signs, dumpsters and a fence were defaced by graffiti, Fairfax County police said.