The arrests, all in Suffolk County, are the result of a nearly two-year county, state and federal investigation — and include nine cell, or "clique" leaders of the violent gang — virtually the gang's entire presence in the county, officials said.

The investigation also thwarted seven Long Island-based murder plots, officials said.

And perhaps most importantly, the investigation prevented the El Salvador-based gang from getting a strong foothold on New York soil, according to Ray Donovan, special agent in charge of the DEA in New York.

"We've learned that through this investigation MS-13 had plans for establishing an East Coast foundation here in New York for the gang, that will never happen," he said.