Nearly 300 members and associates of the infamous transnational drug gang MS-13 have been arrested in an interdepartmental collaboration called Operation: Raging Bull, leadership of the Immigration and Customs Enforcement (ICE) Agency announced Thursday.

Led by ICE Homeland Security Investigations’ (HSI) National Gang Unit, the operation was a multi-phase, multi-month project of numerous federal law enforcement agencies, including ICE, U.S. Customs and Immigration Service, the U.S. Border Patrol, and the Department of Justice. The operation led to a total of 267 arrests of MS-13 members and associates.

In September, ICE announced initial arrests of 53 MS-13 gang members in El Salvador, the product of 18 months of investigation. On Thursday, the results of an additional month of investigation were further revealed.

Over that second phase, between October and November of 2017, 214 members of MS-13 were arrested. 93 of those were arrested on federal or state criminal charges, while the other 121 face immigration violation charges.