(KMOV.com) -- Police have arrested and charged a fourth person after a man's body was found along a hiking trail in St. Clair County late Tuesday evening.
According to the Major Case Squad, the body of 38-year-old Melvin Ashley Gregory was discovered after 7:30 p.m. on Route 163 and Levee, located just outside Centreville, Illinois.
Police say three people discovered Gregory's body on Tuesday when they were horseback riding along the trail.
Evidence at the scene and on the body indicated that Gregory did not die from natural causes. The St. Clair County coroner said Gregory suffered multiple stab wounds to the neck.
Investigators say Gregory got into a confrontation with his girlfriend, Donna Mrkacek, when Dylan Baldwin and Billie Jo Carson stepped in and stabbed Gregory to death. Thirty-two-year old Carson and 26-year-old Baldwin were charged with First Degree Murder.
Mrkacek was charged with concealing homicide and obstructing justice for her alleged involvement in the disposing of evidence and cleaning up the crime scene.
Carson and Baldwin are held on a $1,000,000 bond. Mrkacek’s bond was set at $300,000.
Christopher Mays, 37, from East St. Louis was originally named a person of interest in the case. He was arrested and taken into custody by the Iron County Sheriff and the Pilot Knob Police Chief on Friday evening in Pilot Knob, Missouri. According to police, Mays was arrested for an active felony warrant out of St. Clair County, Illinois for an unrelated offense.
Major Case Squad investigators responded to the Iron County Sheriff's Office and questioned Mays, who was ultimately extradited back to Illinois for the outstanding warrant. On Saturday afternoon, Mays was charged with 1st Degree Murder for the murder of Melvin Gregory.
Mays is currently being held in the St. Clair County jail on a $1-million bond.