Federal immigration and customs officers have arrested more than 1,000 suspected gang members and associates so far this year as part of a nationwide campaign aimed at deporting illegal immigrants with suspected ties to violent criminal organizations, officials said yesterday.

Much like similar efforts after the Sept. 11, 2001, attacks to target suspected terrorist sympathizers, the Department of Homeland Security's anti-gang program seeks to use immigration laws to remove many alleged gang members from the country rather than pursue them through U.S. criminal courts, officials said.

The campaign, dubbed Operation Community Shield and overseen by the Immigration and Customs Enforcement (ICE) division, has resulted in arrests of 1,057 alleged gang members over the past five months -- including 582 suspects apprehended during a concerted push in the last two weeks of July. Eleven of the suspects were arrested in the Washington area, officials said.

The operation got its start in March as a way to target Mara Salvatrucha, or MS-13, a violent street organization active in Northern Virginia and other parts of the South. But the program has quickly expanded to encompass alleged members of 80 gangs in 25 states, including Latin Kings, Asian Boyz and Jamaican Posse.

"Street gangs in America have grown and expanded their influence to an alarming level, marked by increased violence and criminal activity," Homeland Security Secretary Michael Chertoff said at a news conference announcing the results of the operation. "These gangs pose a severe threat to public safety, and their growth must not go unchallenged."

The crackdown comes as part of a renewed concentration on violent street gangs by the federal law enforcement agencies after several years of focusing primarily on terrorism issues.

Attorney General Alberto R. Gonzales is forming a special anti-gang task force, while Congress is debating proposals to lengthen prison sentences for gang-related crimes and to make it easier to deport suspected gang members. The Justice Department estimates that more than 750,000 gang members are active across the United States.

Under the ICE anti-gang program, local and state police departments have supplied federal immigration and customs agents with the names of thousands of suspected gang members. Federal agents are comparing those lists with federal immigration databases to target members or associates who are in the country illegally or who have committed serious crimes that make them eligible for deportation, officials said.

Chertoff said that more than 900 of those arrested so far are eligible for deportation. The rest will probably be prosecuted for crimes including immigration violations and illegal possession of a firearm, officials said.

"I have to say we're surprised by the numbers we're encountering," John P. Clark, deputy assistant secretary at ICE, said in an interview. "Violent gang members have to be on the top of the list of our priorities."

The 11 people arrested in the D.C. area were Northern Virginia-based members or affiliates of MS-13, which is considered the largest and most violent street gang in Northern Virginia. Three will face criminal charges in federal court of reentering the United States after being deported and possessing fraudulent immigration papers, said Allan Doody, special agent in charge of ICE's Washington field office. The other eight are being held for deportation proceedings.

Several of those arrested have convictions on charges such as robbery, assault and battery, and brandishing a firearm, Doody said. Most are in their mid-twenties. He said none is known to have connections to major MS-13 cases that have been prosecuted in federal court in Northern Virginia, such as the murder of Brenda Paz, a 17-year-old federal witness. Federal prosecutors in Alexandria have been investigating MS-13 since at least 2001.

Doody said the 11 people -- nine in Northern Virginia and two in the District -- were arrested between July 19 and July 22.

Staff writer Jerry Markon contributed to this report.

"These gangs pose a severe threat to public safety," Homeland Security Secretary Michael Chertoff said. At right is Marcy Forman of ICE.