NEWARK, New Jersey (AP) — Fourteen reputed members of a violent street gang that federal authorities said has terrorized central New Jersey for years, including through murders, robbery and extortion, were charged in a 26-count indictment unsealed Wednesday.

U.S. Attorney Paul Fishman called the MS-13 gang "an extraordinarily dangerous criminal enterprise whose entire reason for being revolves around imposing its leaders' will through violence and intimidation."

The indictment focused on a sub-unit of MS-13 based in Plainfield called Plainfield Locos Salvatruchas, or PLS. The gang set down roots in the area in the late 1990s and Union County began an investigation after a series of violent incidents in 2009, acting county prosecutor Grace Park said.

According to the indictment, the gang members were responsible for the murders of two rival gang members, a bystander and even a female MS-13 member who allegedly was driven to an industrial site in Piscataway and shot in 2010.

Eleven of the 14 were charged with racketeering conspiracy. As part of the conspiracy, the indictment alleged, PLS members extorted payments from inactive members of the gang and threatened violence against anyone who didn't pay.

Santos Reyes-Villatoro, nicknamed "Mousey," who allegedly helped form the PLS gang in the late 1990s, pleaded not guilty in federal court Wednesday along with 12 other defendants. A final defendant remained at large.

MS-13 originated in Los Angeles among immigrants from El Salvador in the 1970s and '80s and has spread to parts of the U.S. and Central America. Authorities believe hundreds of members live in New Jersey.

Andrew McLees, an Immigration and Customs Enforcement special agent in charge of homeland security investigations, said more than 4,000 MS-13 members have been arrested nationwide since 2006. He called the gang "a ruthless, dangerous and rapidly expanding transnational street gang."

Several avowed members of MS-13 were convicted or pleaded guilty in one of northern New Jersey's most heinous recent crimes, the execution-style slayings of three college students behind a Newark elementary school in 2007.