Retired Fairfax County police officer P.D. O'Keefe faced a cafeteria full of sixth-graders last week and told them how a 16-year-old boy's hands had been mutilated in a machete attack by rival gang members the day before.

One young boy in the audience who has been flirting with gang involvement approached school officials afterward and asked thoughtful questions about gangs. Another simply glared during the entire presentation.

"He's already brainwashed with this idea of gang life," said O'Keefe, who helps run drug and gang prevention programs for the Fairfax school system. "Part of the gang mentality is you have no care for the future -- it's all about today."

Fairfax officials are hoping that what happened to the 16-year-old in the Alexandria area of the county will serve as a wake-up call to the community about a growing, and increasingly violent, gang problem in Northern Virginia in recent years.

Lawmakers and police have significantly bolstered their efforts to contain the problem, stepping up patrols and passing tougher laws and penalties. Although additional resources will help run gangs out of town, the solution to the problem lies closer to home, they say. Parents of the wounded 16-year-old say he was not in a gang. Law enforcement officials say there is compelling evidence that he was.

"When you have parents in the total dark about the son's involvement, that is the greatest challenge," said Maj. Frank Wernlein, who oversees the Fairfax police department's gang unit. "Until we make sure those parents are involved, to me that is the biggest dark shadow we face. Whether it's denial or embarrassment, it's an issue for them."

What happened about 1 a.m. Monday on Edsall Road was the latest in a string of violent gang-related acts that include slayings, rapes and assaults with baseball bats, police say. But the brutality of the act caught the attention of the public, and officials hope it will help residents in the suburbs understand that gangs are not just a city problem.

Fairfax County Supervisor Sharon S. Bulova (D-Braddock), who has been hosting community meetings on gang violence, believes the attack will spark an even greater effort to deter gang violence.

"It's way outside the realm of viciousness for what we know in Fairfax and Northern Virginia," Bulova said. "The whole community was shocked. If anything, this galvanizes us to do more about it."

In an effort to quell further acts of revenge between the two rival gangs, acting Police Chief Suzanne G. Devlin stepped up patrols in areas where gang members are known to gather.

On Thursday night, Fairfax police started using about 10 officers from specialty units, including SWAT team members, in targeted neighborhoods, Wernlein said. And four law enforcement officers from the region's gang task force are working with the county's gang unit of eight detectives and two supervisors to increase the police presence at two carnivals this weekend in Springfield and Annandale, among other areas.

Virginia legislators are so fed up that they passed laws this year that put gangs -- sometimes perceived as something as minor as graffiti artists -- on par with organized crime organizations.

Effective July 1, gang members can be charged with a felony under the Racketeer Influenced and Corrupt Organization Act for operating a criminal venture that generates revenue -- drug running, for instance -- said Tim Murtaugh, a spokesman for Attorney General Jerry W. Kilgore (R). The maximum penalty is 40 years in prison.

Legislators also expanded penalties for gang recruitment. It is illegal for adults to recruit juveniles into gangs, but new laws will make it a misdemeanor for people of any age to recruit gang members.

Police officers will also soon have the authority to detain illegal immigrants participating in a gang; previously many officers freed them upon learning their status "because immigration is a federal issue and they thought their hands were tied," Murtaugh said.

And legislators added machetes to a list of items -- such as pistols and bowie knives -- that cannot be carried concealed.

"Gangs are really spreading, and we need to get on top of this as soon as possible," Murtaugh said. "These are important tools the police hadn't had before. If they're participating in violent crimes you can always charge them with assault, but it didn't seem like the law was addressing the phenomenon of gangs."

Fairfax County Commonwealth's Attorney Robert F. Horan Jr. said he has seen gang-related activity rise and fall during the past decade. Several years ago, he said, members of Asian gangs committed a rash of crimes.

Police said Monday's attack was part of a running feud between Mara Salvatrucha, or MS-13, and the victim's gang, South Side Locos, or SSL. Hayner R. Flores, 18, a reputed MS-13 member, was charged in the attack with malicious wounding and participation in a gang, police said.

In recent years, Horan said, MS-13 has emerged as the most violent active gang. He noted that one reputed MS-13 member who is awaiting trial could face the death penalty if convicted in the rape and beating death of a young mother, who was walking near her Falls Church home when she was accosted.

"With MS-13 we are seeing some heavy violence, and most of it is directed at other gangs," Horan said.

As lawmakers continue efforts to strengthen laws against gang-related crime, school and community officials are trying to deter gang violence and help vulnerable kids avoid the lure of gangs.

In addition to running gang-prevention programs for students, Fairfax schools host programs to help parents and teachers spot possible warning signs of gang involvement, school officials said. The system also is planning training for counselors and school psychologists about techniques to help kids drawn to gang life.

Devlin, the acting police chief, said she hopes the attack will jolt parents into action. She said well-intentioned parents can miss signs of gang involvement.

"Their parents see another side of them. The parents have no idea they are involved in this stuff," Devlin said. "I would say to check your kid's room, read their diaries, look in their cars and figure out what they are doing at night."