Federal prosecutors announced a sprawling indictment Friday against a New Orleans street gang accused of racketeering, trafficking crack cocaine and heroin, and committing at least a dozen murders in the city since 2010.

The gang, said to be known as the 39ers, had a penchant for punishing rivals with a .223-caliber assault rifle, a weapon its members referred to as “Monkey Nuts” because of its double-drum magazine that held more than 100 rounds of ammunition, the U.S. Attorney’s Office said.

The 45-count indictment, handed up last week in U.S. District Court, outlines a murderous reign in which the 39ers frequently traveled to Houston to buy heroin and returned to New Orleans to sell it in the 9th Ward and some of the city’s Uptown neighborhoods.

All 13 defendants, many of whom previously have been charged in state court, are accused of participating in at least one murder apiece. They face life in prison if convicted.

The indictment marks the latest in a series of racketeering cases that authorities have brought against street gangs in New Orleans as part of a targeted effort to bring down the city’s high murder rate, which long has been fueled by the distribution of narcotics and retaliatory gang shootings.

Local and federal authorities combined efforts about three years ago in an initiative known as the Multi-Agency Gang Unit, which seeks to deter gang violence by charging dozens of so-called “co-conspirators” in sweeping federal indictments that typically yield lengthy prison terms.

The authorities have brought similar cases in recent years against the 110ers gang and the alleged Central City crime syndicate run by Telly Hankton.

The unit’s strategy is rooted in the belief that a small number of criminals bear responsibility for a disproportionate percentage of the city’s bloodshed.

The 39ers trace their roots to early 2010, the indictment says, when the G-Strip gang, which operated in the 9th Ward on Gallier Street, joined forces with the 3NG, a crew that controlled territory around the corner of Third and Galvez streets.

The indictment says the gang rented a property in coastal Mississippi, which it used as “a hideout and to store cash profits from the enterprise’s heroin sales.”

The 39ers sought to “circumvent the criminal justice system,” intimidated witnesses and even imposed a system of discipline upon members “who may have acted in a reckless manner by bringing unwanted attention by law enforcement officials,” the indictment says.

In September 2011, the gang caught wind that a man named Michael Marshall had been cooperating with the U.S. Drug Enforcement Administration. The indictment says three gang members — Washington “Big Wash” McCaskill, 36; Leroy “Lee” Price, 29; and Ashton “Pound” Price, 24 — followed Marshall to his place of employment and fatally shot him as he tried to get out of his car. Prosecutors said an assault rifle was used in the attack.

The other alleged gang members charged in the indictment are Alonzo “Woo-dee” Peters, 25; Jasmine “J-Real” Perry, 24; McCoy “Rat” Walker, 25; Terrioues “T-Red” Owney, 28; Evans “Easy” Lewis, 23; Curtis “Pooney” Neville, 22; Rico “Freaky” Jackson, 33; Tyrone “T-Bone” Knockum, 24; Solomon “Black” or “Sol” Doyle, 29; and Damian “AD” Barnes, 27.

The indictment also names a few leaders of the 39ers who were not charged in this document. Merle Offray and Darryl “Brother” Franklin were described as the main drug suppliers to the gang who also “directed members to commit murders.” Another unindicted leader, Gregory “Rabbit” Stewart, also participated in multiple murders, the indictment says.

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