North Texas law enforcement agencies arrested 66 gang members and their associates in a six-day operation that ended Saturday night.

The crackdown is part of a three-year-old national push by U.S. Immigration and Custom Enforcement to target transnational gangs, ICE said Tuesday in announcing the arrests. The foreign-born came from Mexico, El Salvador, Honduras and Laos.

It’s the second largest cluster of alleged gang members nabbed by ICE in North Texas under its Operation Community Shield. Since the initiative began in 2005, more than 13,000 gang members have been arrested, ICE said.

The arrests were made with assistance of police agencies in Arlington, Dallas, Carrollton, Fort Worth, Irving and Lewisville and Plano. The Bureau of Alcohol, Tobacco, Firearms and Explosives also participated.

“It is remarkable the intel we got working with everyone,” said John Chakwin, the ICE special agent in charge of investigations in Dallas.

Among those arrested were six gang members from the Mara Salvatrucha 13, considered one of the most violent transnational gangs by federal officials. Two members of that gang were nabbed in Carrollton, one person in Irving, and the other three in Dallas or Fort Worth, said ICE spokesman Carl Rusnok.

One person, arrested in Fort Worth, was identified by ICE as a member of the Zetas, a drug gang linked to a Mexican narcotics cartel. Another 22 gangs were represented among those arrested, ICE said.

About a third of those arrested were U.S. citizens, ICE said. Fourteen of the 66 were deemed “gang associates.” And 15 people were picked up on administrative immigration charges, bringing the total number of arrests to 81.