An MS-13 gang leader whose brutality a federal prosecutor described as “almost unfathomable” has been sentenced to life in prison for conspiracy to commit murder in the aid of racketeering and other charges.

Miguel Angel Corea Diaz, 41, also known as “Reaper,” was once the highest ranking MS-13 member on the East Coast, the U.S. Department of Justice said Friday.

The life sentence was imposed after Corea Diaz, of Long Branch, New Jersey, was convicted by a federal jury in November of conspiracy to commit murder in the aid of racketeering, murder in the aid of racketeering, drug dealing conspiracy and possession with intent to distribute controlled substances, according to federal prosecutors.