RIO GRANDE CITY – A fourth suspect in connection with the death of Rio Grande City teen, Chayse Olivarez, was formally charged at the county level Tuesday afternoon.

Salvador Martinez, 18, is charged with tampering with evidence and tampering with a human corpse.

He pleaded not guilty to the charges against him.

Olivarez disappeared in late July. His body was found early August on a ranch in Roma.

Investigators said the crime is rooted in personal issues between the suspects and victim.

Martinez's bond is set at $750,000. A pretrial date is set for January.