Six bodies found in one month in Brentwood. Sources say the Central American gang MS-13 is suspected in many of the murders.

News 12 Long Island's Eileen Lehpamer and photojournalist Brian Endres hit the streets with Nassau and Suffolk's gang unit detectives to find out more about the gang.

Suffolk police tell News 12 Long Island that the Salvadorian gang MS-13 is suspected of 10 murders in the county this year.

"They want to be feared, they want everybody to know, that they're the toughest, the baddest," says retired Suffolk Detective John Oliva.

According to a law enforcement handbook, MS-13 makes money through theft, robberies and extortion. They demand "protection money" from local store owners. But unlike other gangs, Oliva says MS-13 members work day jobs.

Gang experts tell News 12 Long Island that MS-13 members use those salaries to pay membership fees to the gang. It's done every few weeks during regularly scheduled meetings, known as "universals." A few years ago, those meetings were held out in the open, along the sidelines at soccer games. Now, the meetings have moved into wooded areas, according to officials.

Nassau detectives George Hoeler and George Colby say gang members don't always wear gang colors or have obvious tattoos and are very strategic about avoiding prosecution.

"The older gang members are making the younger gang members do all the violence, shootings and stabbings, because they know they're a juvenile, and they're not going to do time," says Colby.

Nassau County police say there are 3,000 gang member and associates currently living in the county. Suffolk Police say there are currently 1,872 gang members and associates living in the county. Nassau police say they don't have a current number for how many belong to MS-13. Suffolk police say that MS-13 has about 500 members or associates in their county.