"Over the past several months, numerous investigative measures were utilized to identify the individual responsible for the double homicide," state police said Wednesday.
Investigators have said Mock, 18, and Caraballo, 15, had gone to the wooded area in New Philadelphia known as "the Sanchez" to go target shooting with two other people on Oct. 8.
The four "remained in the area for a short period of time" before Mock was fatally shot in the head and Caraballo was stabbed to death, according to authorities.
Branch, 19, of Port Carbon, was denied bail, court records show. He has a preliminary hearing scheduled for June 11.
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