Successful programs have been developed that effectively keep teenagers out of gangs and significantly reduce youth homicides, a study released yesterday by law enforcement agencies and crime victims shows.

But the White House is proposing to cut funding for the specific programs by 40 percent in the next fiscal year, in addition to a 44 percent reduction in anti-gang and delinquency funding this year, the national study said.

Established street gangs are "migrating from Chicago and Los Angeles, and coming soon to a town near you, I can promise you," Los Angeles Police Chief William J. Bratton said in a telephone conference on anti-gang funding that included acting Fairfax County Police Chief Suzanne G. Devlin.

"The federal government is literally feeling the war on crime has been won and is putting their resources elsewhere," Bratton said. "The war on crime has not been won. We need programs that the federal government is preparing to cut funding for." Law enforcement officials estimated that cuts in anti-gang programs would total about $127 million in the next fiscal year.

Chad Kolton, a spokesman for the Office of Management and Budget, said the government is redirecting funding to another more effective program and is proposing a new program, with $53 million in additions to partially offset the $127 million in cuts.

"We have redirected a substantial amount of resources to focus our efforts better on preventing juvenile delinquency," Kolton said. He said the net reduction in anti-gang funding was the result of shifting funds to counterterrorism programs.

Members of Fight Crime: Invest in Kids, a Washington-based nonprofit group of 2,500 police chiefs, sheriffs, prosecutors and crime victims, arranged the phone conference to call attention to its new report highlighting programs designed to prevent gang violence.

Although gang-related homicides rose more than 50 percent nationally from 1999 to 2002, prevention programs in Boston, Philadelphia and Baton Rouge have produced dramatic results. Youth homicides were down by two-thirds in Boston and by more than 40 percent in two districts in Philadelphia; and 80 percent fewer violent crimes were committed by youths as a result of an anti-gang project in Baton Rouge, the study found.

The programs focus on preventing gang involvement by funding youth mentors, parent counselors, more active probation supervision and job opportunities. In addition to police, social services and community groups monitor youths who are at risk of gang involvement and steer them down a safer path. The programs can start as early as pre-kindergarten, said Sanford A. Newman, president of Fight Crime.

But teenagers generally are the focus, including those already involved in gangs. Arrest and prosecution are still integral parts of the approach, Newman said.

"When we combine identifying these gang leaders and letting them know there will be serious swift consequences and link them to mentors and job training, that can drastically cut crime," Newman said.

In suburban Fairfax, which has dealt with a recent gang-related slaying in Herndon and a brutal machete attack in the Alexandria area, Devlin said the county has charted 82 gangs and more than 3,000 members. "As cities get more effective at dealing with this," Devlin said, "it displaces the crime out to suburban and rural jurisdictions."

Fairfax officials said they were not facing an immediate loss of anti-gang funding. But Devlin said that even if Fairfax were facing cuts, she would rearrange funds so that anti-gang resources were not affected. Fairfax has a gang unit with eight full-time officers, and a regional gang task force operates out of Herndon.

James A. Fox, a criminologist at Northeastern University, said national statistics showing little change in violent crime have masked "a sharp increase in gang homicides." He said gang-related killings declined in the 1990s, "then increased in 1999, when we let down our guard, when we thought the gang problem disappeared."

Because street gangs often involve juveniles, Fox noted, a new crop of potential members appears every five years or so. "Prosecution has a short-term effect," he said. "Prevention has a long-term effect."

Fight Crime officials said $547 million was budgeted for anti-gang programs in fiscal 2002. That amount dropped to $307 million in 2004 and is slated to drop to $180 million in 2005 -- a 67 percent reduction in three years. Among the biggest programs slated for cuts are Title V local delinquency prevention grants, which will be reduced from $79 million to $37 million, and Juvenile Accountability Block Grants, reduced from $60 million to zero. Philadelphia used some of the juvenile accountability grants in its drive to reduce youth slayings in two of its most violent districts.

Kolton said the administration reviewed the juvenile accountability program and found it ineffective and inflexible. He said a program proposed by the White House focuses on mentoring, after-school tutoring and substance abuse and would fund programs "that can most effectively meet their mission."

But Kolton acknowledged the net reduction in funding, saying, "We've reevaluated our priorities. We've provided substantial resources in funding to deal with counterterrorism. But we've also continued to put a good deal of resources into programs to deal with juvenile delinquency and domestic crime issues."

Congress is expected to deal with the funding proposals as early as next week.

Los Angeles Chief William J. Bratton, painting over gang graffiti with Jonathon Ortega in 2002, opposes federal budget cuts that have hit anti-gang programs.Gangs are moving from the city to the suburbs, says Suzanne Devlin, acting Fairfax County chief.