Updated

Authorities in the Washington D.C. metropolitan area are concerned that the surge of unaccompanied migrants coming across the United States’ southern border could be helping the notorious MS-13 street gang recruit new members and is fueling a spat of violence around the nation’s capital.

There are no hard numbers on how many of these unaccompanied minors have joined up with MS-13. But three alleged MS-13 members who were charged in September of last year in connection to the murder of a 17-year-old were identified as entering the country illegally in 2013 – when the border surge was at its peak – and skipping out on their immigration hearings.

“History dictates the way gangs recruit,” Ed Ryan, the gang prevention coordinator in Virginia’s Fairfax County told Fox News Latino. “They always prey on kids who are new to an area or are looking for someone who they can relate to.”

MS-13 was founded more than two decades ago in Southern California by immigrants fleeing El Salvador's civil war. Its founders took lessons learned from the brutal conflict to the streets of Los Angeles, as they built a reputation as one of the most ruthless and sophisticated street gangs in the country.

The have since spread throughout their home nation and helped El Salvador become the country with the fourth highest per capita murder rate in the world, according to the United Nations Office on Drugs and Crime.

A large wave of Salvadorans entering the U.S. has helped the gang spread from their roots in Los Angeles and El Salvador to many pockets of the U.S.

Outside of Los Angeles, the Washington, D.C. metropolitan area has the largest Salvadoran population in the U.S., at just over 228,000.

"MS-13 functions like all immigrant organized crime group, they start by targeting their own community," Lou Gentile, a former officer at the Organized Crime Unit of the Pennsylvania State Police and founder of the investigative firm CSI, told FNL.

With as many as 10,000 members in 46 states, MS-13 has also diversified its operations from a violent street gang, with members being convicted of crimes ranging from kidnapping and murder to drug smuggling and human trafficking.

In D.C., 13 purported MS-13 members will appear in federal court this week after allegedly carrying out killings in 2013 and 2014 in an effort to maintain or increase the gang’s power in Washington area.

“What we are beginning to see is an attempt to re-establish themselves as the preeminent gang in the Maryland area.” John McCarthy, the state attorney for Maryland’s Montgomery County told the Washington Times. “They are actively trying to build their numbers again. That is based on direction they are receiving from outside the U.S.”

One of the group’s biggest rackets has been in the human trafficking of underage age girls to work in brothels.

Gang members prey on younger girls in much the same way they do when recruiting new members – offering them money and material goods to become involved in the illicit trade. While the involvement in the sex trade has kept the levels of violence down to an extent over the last few years, officials in the Washington D.C.-area have said they are seeing disturbing hints that violent crime tied to the organization could be on the rise.

“There has definitely been more violence this year,” Ryan said.

Ryan, who works mainly with juvenile offenders and other at-risk youth, said one of the most difficult parts of his job is identifying which of the youth he sees are actually involved with the gang.

“They’re getting smart now. They don’t use tattoos or other ways to identify someone as a gang member that much anymore,” he said. “I can count on one hand the number of kids who have told me they are full-fledged members of a gang.”