An 18-year-old has been charged with murder in connection with the MS-13-related killing of a Fairfax County teen in August 2017, bringing the total number of people arrested in the case to six, authorities said.

Prince William County police did not identify the 18-year-old because he was charged as a juvenile. He was a minor at the time of the alleged slaying of Miguel Angel Ruiz Carrillo, 18.

The 18-year-old suspect had been incarcerated in Fairfax County on unrelated charges, before he was transferred to the Prince William County jail late Monday or early Tuesday, police said.

Carrillo, who had ties to MS-13, met gang members in some woods near his home in the Mount Vernon section of Fairfax County in August 2017, according to a search warrant filed in Fairfax County.

Carrillo was assaulted, driven from the scene and not heard from again, according to the search warrant. Carrillo’s body was discovered in Nokesville later that month, and a handful of people have been charged with murder, abduction and gang participation in connection with the slaying.