INDIANA, Pa. (AP) — Authorities say eight people have been arrested in the case of a 19-year-old man taken from his western Pennsylvania home last week and later found stabbed to death in a rural area.

State police and prosecutors in Indiana County said seven adults ranging in age from 18 to 21 were taken into custody on charges of kidnapping to facilitate a felony and/or conspiracy in the death of 19-year-old Hayden Garreffa. A 14-year-old girl was also arrested.

“Criminal homicide charges will be filed pending further investigation,” Trooper Cliff Greenfield told reporters Tuesday.

Greenfield said Garreffa was staying with a relative in Buffington Township and was taken away from there in a minivan Thursday. He said the victim was autistic and departed without his cellphone and medication, both of which “he never would have left behind.”

His body was found two days later in Brush Valley Township with stab wounds in the upper body, neck and head.

District Attorney Robert Manzi Jr. and Greenfield declined to discuss a possible motive for the crime.