Alexi Saenz appeared before a judge in federal court in Central Islip.
Saenz pleaded guilty to the brutal killings of two teenage girls, Kayla Cuevas and Nisa Mickens, back in September 2016 in Brentwood.
Prosecutors say Saenz and his brother Jairo hunted the best friends down and attacked them with machetes and beat them with baseball bats.
The deaths of the innocent victims made headlines around the country. Their murders and the later discovery of many other buried bodies on Long Island prompted federal law enforcement to help local police crack down on MS-13 on Long Island.
The U.S. Department of Justice at the time called it their war on MS-13.
Back in 2020, the feds said they would seek the death penalty against Saenz, however, in 2023, Eyewitness News is told Attorney General Merrick Garland instructed prosecutors to back off from that.
Charges against Jairo remain pending.