With law enforcement focused on terrorism, gang-related bloodshed on America’s streets is rising to levels not seen since the mid-1990s, when the crack epidemic was still raging, authorities say.

Homicides are up sharply this year in cities such as Los Angeles, Oakland, Calif., and Little Rock, Ark., a surge attributed largely to gang members killing each other or those caught in the crossfire.

“We had a stranglehold on it and we allowed them to breathe. We relaxed our grip and now they’re back,” said Wes McBride, president of the California Gang Investigators Assn. The now-retired McBride spent 28 years on gang detail with the Los Angeles County Sheriff’s Department.

Other major cities, including Philadelphia, New York and Miami, are seeing a decline or little change in homicides this year. And bloodshed in the cities with rising death tolls is still considerably lower than it was during the very peak of the crack trade in the early 1990s.

But many fear the cycle is only beginning.

“It’s too easy given today’s terrorism and other security issues to ignore a continuing problem in places like Los Angeles, but it could become worse than it’s been in the last six years,” said John Moore, director of the Tallahassee, Fla.-based National Youth Gang Center. “It’s gotten more violent and more intense.”

Many cities had record homicide numbers in the early 1990s, then saw a dramatic decline over the second half of the decade, credited in part to police pressure on gangs, the strong economy and a waning crack trade.

The resurgence over the past two years is being blamed on a number of factors, including the weak economy and gang members getting out of prison. Also, law enforcement has been devoting more attention to terrorism and some police departments let down their guard against gangs because the problem seemed under control.

“All of these big cities had gang units but abolished them as if to say the gang problem went away,” said George Knox, director of the National Gang Crime Research Center in Peotone, Ill. “We definitely left a lot of hot spots out there.”

Los Angeles had the nation’s highest death toll as of Dec. 1, with 617 homicides. The last time the city had that many slayings was in 1996, when the year-end total was 707. The city saw 35 people killed during the last two weeks of November in a spasm of mostly gang-related violence.

L.A. Police Chief William Bratton is looking to federal prosecutors for help in fighting gangs with some of the same weapons used against the Mafia: racketeering and tax evasion laws.

“What’s going on now is the job market is much tighter, so there’s less opportunity for people who are coming out of their teenage years to move into jobs,” said Alfred Blumstein, a Carnegie Mellon University professor and director of the National Consortium on Violence Research.

“And there’s a greater anxiety, partly because of the economy, partly because of terrorism, and there may be a resurgence in drug markets that may be fueling violence.”