Federal law enforcement officials in states around the country are targeting the criminal organization known as MS-13, a violent street gang with origins in Central American countries.

In September, police in Oregon and Minnesota arrested suspected gang members, some accused of violent crimes.

In Northern Virginia, where police estimate there are over 2,000 members, a 17-year-old Herndon High School student was stabbed to death by an MS-13 gang member who pled guilty to the crime.

MS-13, which stands for Mara Salvatrucha, is a mainly Central American gang whose original members arrived in Los Angeles and Washington, D.C. in the 1980s after 1 million people fled a vicious civil war in El Salvador.

In Los Angeles, the refugees flocked to an established Hispanic neighborhood known as the "Rampart." But the area's predominantly Mexican population did not welcome the Salvadorans and subjected them to discrimination and the abuses of local gangs.

In response, refugees with paramilitary or guerilla experience from their days in El Salvador banded together to form the Mara Salvatrucha gang. The gang's name is derived from the Spanish word for army ant, marabunta, and Salvatrucho, which is the nickname Salvadorans use to refer to themselves.

"Most of these members coming from the war-torn countries where, you know, killing was a regular occurrence -- violence, beating people up, stabbing people, seeing people die. I mean, they were desensitized. So, when it came time for them to deal with rival gang members, I mean, their readiness to commit a violent act was nothing; it was second nature," officer Frank Flores, a member of an anti-gang unit of the L.A. Police Department, told the NewsHour.

Gang members typically used tattoos to identify themselves and graffiti to indicate their turf.

Common markings for both include "MS," "Salvadorian Pride" and the number "13," which has superstitious and gangland connotations.

The FBI estimates that MS-13 has as many as 10,000 active members dispersed in 33 states. Members have been accused of burglaries, drug sales, weapons smuggling, extortion, illegal firearm sales, auto thefts, murder and rape.

MS-13 also has developed a reputation around the world.

In August, coordinated attacks by MS-13 members in seven Guatemalan prisons left 35 inmates dead. And, last year, 28 people died when MS-13 members sprayed a bus in Honduras with automatic weapon fire.

To combat the MS-13 threat, the federal government has initiated a nationwide campaign called Operation Community Shield, part of the Department of Homeland Security's anti-gang program.

So far in 2005, immigration and customs officers have arrested 1,057 suspected gangsters.

Congress also has begun working on legislation to make gang crimes federal offenses with mandatory minimum sentences, after rumors surfaced that MS-13 may have had connections to al-Qaida.

"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 has said.

"These gangs pose a severe threat to public safety, and their growth must not go unchallenged."

Homeland Security initially planned its offensive specifically to counter Mara Salvatrucha but has since targeted all 750,000 active gang members the Justice Department estimates make up 80 gangs in dozens of states.

Some community activists say more arrests are not the answer.

"It's not solving the problem. It's just the putting a bandage over the problem, you know, because you're not dealing with the real root cause of the problem," says Alex Sanchez, a former gang member who now helps organize Homies Unidos, an intervention program with offices in L.A. and El Salvador.

"You still have kids joining gangs as small as, you know, junior high. And you have kids that are in elementary already knowing, you know, the gang structure and already knowing about gangs," Sanchez adds.

MS-13 gang members deported from the United States have spread to Ecuador, Guatemala, Honduras and Mexico, where governments are cracking down. Human rights groups have complained that innocent people have been jailed, and that prisons are overcrowded.

Those who return to El Salvador face a grim future. The official government policy of President Elias Antonio Saca is "super mano dura," or super hard hand.

The national police force includes heavily armed soldiers, and the government imprisons any person found with gang-related tattoos, even if they are not caught participating in criminal activity.