Membership estimates in the US vary between 8,000 and 50,000 (link) Probably somewhere in the middle.

Justice Department Releases MS-13 Threat Assessment
by Jim Kouri, CPP
January 15, 2008

They've severed the fingers of their rivals with machetes...brutally murdered suspected informants, including a 17-year-old pregnant federal witness...attacked and threatened law enforcement officers...committed a string of rapes, assaults, break-ins, auto thefts, extortions, and frauds across the US...gotten involved in everything from drug and firearms trafficking to prostitution and money laundering...and are sowing violence and discord not just here in the US but around the world.

MS-13 members perpetrate violence—from assaults to homicides, using firearms, machetes, or blunt objects—to intimidate rival gangs, law enforcement, and the general public. They often target middle and high school students for recruitment. And they form tenuous alliances...and sometimes vicious rivalries...with other criminal groups, depending on their needs at the time.

Who are they? Members of Mara Salvatrucha, better known as MS-13, who are mostly Salvadoran nationals or first generation Salvadoran-Americans, but also Hondurans, Guatemalans, Mexicans, and other Central and South American immigrants. And according to our recent national threat assessment of this growing, mobile street gang, they could be operating in your community...now or in the near future.

Based on information from our own investigations, from our state and local law enforcement partners, and from community organizations, we´ve concluded that while the threat posed by MS-13 to the US as a whole is at the "medium" level, membership in parts of the country is so concentrated that we've labeled the threat level there "high."

Here are some other highlights from the FBI's MS-13 threat assessment:

MS-13 operates in at least 42 states and the District of Columbia and has about 6,000-10,000 members nationwide. Currently, the threat is highest in the western and northeastern parts of the country, which coincides with elevated Salvadoran immigrant populations in those areas. In the southeast and central regions, the current threat is moderate to low, but recently, we've seen an influx of MS-13 members into the southeast, causing an increase in violent crimes there.

MS-13 members engage in a wide range of criminal activity, including drug distribution, murder, rape, prostitution, robbery, home invasions, immigration offenses, kidnapping, carjackings/auto thefts, and vandalism. Most of these crimes, you'll notice, have one thing in common—they are exceedingly violent. And while most of the violence is directed toward other MS-13 members or rival street gangs, innocent citizens often get caught in the crossfire.

MS-13 is expanding its membership at a "moderate" rate through recruitment and migration. Some MS-13 members move to get jobs or to be near family members—currently, the southeast and the northeast are seeing the largest increases in membership. MS-13 often recruits new members by glorifying the gang lifestyle (often on the Internet, complete with pictures and videos) and by absorbing smaller gangs.

Speaking of employment, MS-13 members typically work for legitimate businesses by presenting false documentation. They primarily pick employers that don't scrutinize employment documents, especially in the construction, restaurant, delivery service, and landscaping industries.

Right now, MS-13 has no official national leadership structure. MS-13 originated in Los Angeles, but when members migrated eastward, they began forming cliques that for the most part operated independently. These cliques, though, often maintain regular contact with members in other regions to coordinate recruitment/criminal activities and to prevent conflicts. We do believe that Los Angeles gang members have an elevated status among their MS-13 counterparts across the country, a system of respect that could potentially evolve into a more organized national leadership structure.

The FBI has been placing more and more resources on the front lines of the MS-13 problem. There are an estimated 10,000 MS-13 gang members in the US and five times as many in the countries that attended the conference.

In 2004, the FBI created the MS-13 National Gang Task Force. In 2005, the FBI helped create a National Gang Information Center and outlined a National Gang Strategy for Congress. Last year, the MS-13 task force coordinated a series of arrests and crackdowns in the US and Central America that involved more than 6,000 police officers in five countries. Seventy-three suspects were arrested in the US; in all, more than 650 were taken into custody.

Jim Kouri, CPP is currently fifth vice-president of the National Association of Chiefs of Police and he's a staff writer for the New Media Alliance (thenma.org). Kouri also serves as political advisor for Emmy and Golden Globe winning actor Michael Moriarty. His book Assume The Position is available at Amazon.Com.
More information on MS-13
History and Growth
Inside Prison