Jairo Guerrero-Bautista, 21, of Reading, was found guilty on three counts of first-degree murder and conspiracy, said the District Attorney's Office.
Investigators say he conspired with Jonathan Torres and two other unidentified men to kill Marli Alonso, Omar Harris, and Joel Cintrón on Dec. 12, 2018.
Alonso, 18, Harris, 20, and Cintrón, 19, were killed on the 600 block of Moss Street, according to police.
Guerrero-Bautista remains in the Berks County Prison ahead of his sentencing hearing on April 9, the DA's Office added.
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