Robert Mickens speaks with reporters outside the U.S. District Courthouse in Central Islip, N.Y., on Friday, April 28, 2017. His daughter, Nisa Mickens, was one of two teenagers who were beaten and slashed to death in September 2016 in a suspected MS-13 gang killing in Brentwood, N.Y. He and his wife, not pictured, met Friday with U.S. Attorney General Jeff Sessions to discuss efforts to stem gang violence in their Long Island community. (AP Photo/Frank Eltman)
Robert Mickens speaks with reporters outside the U.S. District Courthouse in Central Islip, N.Y., on Friday, April 28, 2017. His daughter, Nisa Mickens, was one of two teenagers who were beaten and slashed to death in September 2016 in a suspected MS-13 gang killing in Brentwood, N.Y. He and his wife, not pictured, met Friday with U.S. Attorney General Jeff Sessions to discuss efforts to stem gang violence in their Long Island community. (AP Photo/Frank Eltman) Credit: Frank Eltman

BRENTWOOD, N.Y. — Late at night, when helicopters thrum overhead and spotlights beam down onto lawns, many people here know exactly what’s going on.

“You just think, ‘Oh, God, whose child is it now?’” said Stephanie Spezia, a longtime resident of this suburb in the heart of Long Island that’s caught in the grip of a violent street gang with Central American ties, MS-13.

MS-13 has been blamed for a trail of 11 corpses of mostly young people discovered in woods and vacant lots in Brentwood and neighboring Central Islip since the start of the school year.

The bloodshed in the blue-collar towns has gotten the attention of President Donald Trump, who says it’s the result of lax immigration policies that let too many criminal “scum” slip through.

Attorney General Jeff Sessions on Friday gave a speech about the violence to law enforcement officials near a park where the bodies of four young men were found this month bearing MS-13’s hallmarks: repeated slashes from a blade that left them nearly unrecognizable.

Some parents say they’re afraid to let their children go to school. Teens say any perceived slight to a gang member, especially a refusal to join, can mean death.

After one high school warned parents not to let their kids wear anything gang-affiliated, gang members started deciding on a daily basis what colors were off-limits, leaving students to guess what not to wear.

So how does a street gang with ties to Central America gain such an aggressive foothold in the suburbs of Long Island?

MS-13, or the Mara Salvatrucha, is believed by federal prosecutors to have thousands of members across the U.S., primarily immigrants from Central America. It has a stronghold in Los Angeles, where it emerged in the 1980s as a neighborhood street gang.

But its true rise began after members were deported back to El Salvador in the 1990s. There, the gang thrived and spread to Honduras. MS-13 and rival groups there now control entire towns, rape girls and young women, massacre students, bus drivers and merchants who refuse to pay extortion and kill competitors.

That violence has prompted a migration of people trying to escape.