"They have a vise grip on the neighborhood, and we are going to release that grip this morning," LAPD Deputy Chief Kirk Albanese said, referring to the Rolling 40s street gang.
Agents and officers went to 47 locations, serving arrest warrants for 74 people charged with federal or state crimes, mostly involving drugs or weapons. More than 30 have been indicted on federal charges that could carry sentences ranging from 20 years to life, FBI spokeswoman Laura Eimiller said.
The sweep, the culmination of an 18-month investigation, netted several gun seizures and 48 arrests by late morning, authorities said. The suspects were handcuffed and taken to Exposition Park, where they waited in a parking lot to be bused to jail.
"Families get to raise their children, send the kids to school, without as much fear involving this particular street gang. ... The communities are held hostage, in a sense," Albanese said.
Eimiller said well over 500 people have been arrested since May in 10 Southern California anti-gang sweeps involving federal and local officials.
Thursday's operation also took place in the midst of a nationwide series of raids against a Mexico-based drug cartel.
Over the past two days, more than 300 people have been arrested in more than a dozen states, including California. The arrests are aimed at the U.S. operations of the La Familia Mexican drug cartel.
The Los Angeles gang sweep was unrelated, Eimiller said.
"This is a local ... violent street gang. They were targeted in this investigation based on the level of violence," Eimiller said.
In recent years, federal, state and local officials have staged a series of crackdowns against street gangs they accuse of running drugs and terrorizing neighborhoods with drug sales, robberies and killings.
Last week, federal immigration announced nearly 300 people had been arrested in the Los Angeles area during a six-month national anti-gang operation that ended Sept. 30.
Los Angeles and other Southern California communities also have used court orders to bar reputed gang members from activities that otherwise would be considered legal, such as gathering in public or flashing alleged gang signs.
More than 40 preliminary injunctions bar members of 71 gangs from gathering in certain Los Angeles neighborhoods.
Civil rights groups have expressed concern over the breadth of such injunctions, but authorities say they are useful in breaking the hold of street gangs on neighborhoods.