A 34-year-old was lured to woods in suburban Maryland, where assailants armed with knives had already dug his grave. A 22-year-old, also taken into a wooded area, was ordered to his knees and shot in the face. An 18-year-old, ambushed near a stream, was stabbed and stoned as he crawled into the water and died under a bridge of the Capital Beltway.

The shocking slayings 18 months ago signaled a resurgence in Montgomery County of the notorious MS-13 gang. Now, with federal racketeering cases underway for three suspects arrested in connection with the killings, court documents lay out a brutal chain of command that law enforcement says drives the violence.

Organized in local MS-13 units called “cliques,” the Maryland gangs put prospective members under long periods of “observations” before allowing them in. Ascension in the gang involves at least five rank designations, according to federal court records, with clique leaders using social media and coded words to stay in constant contact with superiors in the United States and El Salvador.