WASHINGTON – The Obama administration declared the ultra-violent street gang MS-13 to be an international criminal group on Thursday, an unprecedented crackdown targeting the finances of the sprawling U.S. and Central American gang infamous for hacking and stabbing victims with machetes.

The Treasury Department formally designated MS-13, or Mara Salvatrucha, a transnational criminal organization. The aim is to freeze it out of the U.S. financial system and seize what are estimated to be millions of dollars in criminal profits from drug and human smuggling and other crimes committed in this country.

The gang was founded by immigrants fleeing El Salvador's civil war more than two decades ago. Its founders took lessons learned from that brutal conflict to the streets of Los Angeles and built a reputation as one of the most ruthless and sophisticated street gangs, according to Immigration and Customs Enforcement Special Agent Jason Shatarsky.