The victims were just 16 and 19 years old.
Authorities say Kevin Lopez-Morales was taken from an immigration hold into Nassau County police custody, charged in the deaths of Angel Soler and Josue Amaya Leonor.
Soler's body was found in October 2017 in a wooded area. He was attacked and killed with a machete, and Lopez-Morales is the fifth man to be charged in his murder.
Leonor's body was found in the Roosevelt Preserve in May of 2018, but police believe he was killed two years ago by as many as seven members of the same MS-13 "Hollywood" Clique.
"The message is clear, we will be unrelenting of this gang," Nassau County District Attorney Madeline Singas said. "We'll be unrelenting in our pursuit of these individuals. They will be held to account."
Police say both victims were perceived to be members of a rival gang, but Leonor's tearful sister told Eyewitness News Friday that her baby brother was no gang member and that he enjoyed soccer and wanted to be a detective.
"Maybe they got confused because of his soccer uniform, which was red and white," Claudia Erazo said through a translator. "But my brother was not affiliated with a gang. I know for sure that my brother was not a gangster."
Jose Daniel Lopez, 19, was also charged in both murders, and more arrests are possible.
"We're still looking to charge people with Leonor's murder," Nassau County Homicide Commander Detective Lieutenant Stephen Fitzpatrick said. "But I think we've taken a big chunk out of them, where we have them on the defensive I believe."
WATCH Friday's morning's news conference on the arrest
The Nassau County Office of Immigrant Affairs helps the county's large immigrant or foreign-born population navigate the criminal justice system, encouraging immigrants to cooperate with law enforcement, and providing aid to limited-English speakers who are witnesses to or victims of crimes.
If teens feel pressured to join gangs, they can CLICK HERE for help.
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