Feds: MS-13 member sentenced for role in Brentwood killing

An MS-13 gang member was sentenced Tuesday to more than 27 years in federal prison for his role in the killing of a man found dead on the grounds of an abandoned psychiatric hospital in Brentwood, federal prosecutors said.

Nelson Argueta-Quintanilla, 25, formerly of Central Islip, pleaded guilty in September 2021 to racketeering and admitted his involvement in the death of Oscar Acosta, along with a subsequent attempt to shoot and kill rival gang members on Lukens Avenue in Brentwood.

“Demonstrating the defendant’s complete disregard for human life, today’s sentence is a fitting punishment for a brutal murder followed by another reckless shooting,” said Breon Peace, U.S. attorney for the Eastern District of New York.

Bobbi Sternheim, Argueta-Quintanilla's Manhattan-based defense attorney, did not respond to a request for comment.

MS-13 members targeted Acosta because, after previously associating with the gang, he began spending time with the rival 18th Street gang, prosecutors said.

On April 29, 2016, a group of MS-13 members, including Argueta-Quintanilla, gathered in a wooded area near a Brentwood elementary school, where they repeatedly struck Acosta with a large tree branch, knocking him unconscious, prosecutors said.

MS-13 members then tied Acosta's hands and feet together, put him in the trunk of a car, drove to a secluded wooded area in Brentwood and took turns striking him with a machete, authorities said.

They then put Acosta in a shallow grave, covered him with dirt and fled, prosecutors said. His body was discovered months later when police were searching for a different MS-13 homicide victim.

Separately, on Aug. 10, 2016, Argueta-Quintanilla and other MS-13 members allegedly opened fire on individuals they believed were members of the Goon Squad, a rival gang, outside a home in Brentwood.

One of the shots went into an adjacent house and struck the headboard of an elderly woman’s bed, records show. No one was injured.

Argueta-Quintanilla was arrested in 2018.