WAYNESBORO, Tenn. -- A Wayne County woman accused of killing her ex-husband with a meat tenderizer mallet was charged with murder Monday.

Officials said 66-year-old Margaret Louise McCoy was originally charged with aggravated assault after her ex-husband, Michael Clayton McCoy, died Saturday morning.

District Attorney General Mike Bottoms said the charges against Margaret McCoy were upgraded Monday to second-degree murder. That decision was made after the victim's death was ruled a homicide by the Tennessee Department of Forensic Sciences.

Second-degree murder is a Class A felony punishable by 15 to 60 years in prison if convicted.

Wayne County Sheriff Ric Wilson said findings of a preliminary autopsy conducted on the 65-year-old Lutts, Tenn., man indicated injuries he sustained in a recent assault resulted in his death.

A family member found the severely beaten victim Friday at his ex-wife's house on Tennessee 69 in Lutts, Wilson said. He was taken to a Jackson hospital, where he died.

Authorities said the victim had scratches, cuts and bruises all over his body.

Wilson said Saturday that authorities believed the victim was beaten with some type of kitchen utensil. He declined, however, be more specific. He added evidence was taken from the house and sent to forensics for examination.

Sources with direct knowledge of the case said Monday that the weapon was a meat tenderizer mallet. They said forensics experts were able to match marks found on the man's body with the mallet.

The sheriff said deputies were called to the residence Friday for a welfare check. When deputy Cliff Adams arrived, he found family members trying to get Michael McCoy into a vehicle so he could be transported to a medical facility.

The sheriff said the McCoys were divorced but had been living together at Margaret McCoy's residence. He said it's unclear when they divorced or how long they had been living together.

Deputies determined that Margaret McCoy was the only other person at the residence when the assault occurred.

Law enforcement records indicate the couple have a history of domestic violence. In fact, authorities said the victim was arrested Jan. 18 for domestic violence.

Wilson said Margaret McCoy is still being held in the Wayne County Jail without bail. She is scheduled to be arraigned today in the courtroom of General Sessions Judge James Ross.

Tom Smith can be reached at 740-5757 or tom.smith@timesdaily.com.