SPRINGFIELD, Ill. (WAND) - Murder charges have been filed against a Sangamon County Jail inmate. 

Court records show the three first-degree murder charges are against 32-year-old Springfield man Isadore H. Montgomery IV. He is accused of killing Markies L. Jones, whose body authorities found on the night of June 5 in a car in the 1600 block of Springfield's S. 11th St. 

Autopsy results showed a gunshot wound claimed the life of Jones, who is from Springfield. 

Montgomery also faces charges of unlawful possession of a weapon by a felon and being an armed habitual offender. On June 19, he went into jail on manufacturing or delivery of a controlled substance and possession of a controlled substance counts. 

The suspect was arraigned Wednesday in Sangamon County court.Â