A St. Louis woman, found in an embankment in Bethalto, died from a gunshot wound to the head, Madison County Sheriff's Department Maj. Brad Wells said Sunday after the autopsy.

Wells, deputy commander of the Major Case Squad of Greater St. Louis, said investigators are making good progress in the investigation into the death of Tabitha L. Milton-Rush.

"To ease the public's mind ... we believe this is a situation where the victim knew the offender and this is not a random act of violence," Wells said.

Police said Saturday it appears Milton-Rush, 44, of Aubert Avenue, was murdered, and her body dumped at the embankment.

Someone found the body about 9 a.m., near the area of Illinois 255 and Illinois 140.

Police said Sunday night they have one person in custody and plan to present the case Monday to the Madison County State's Attorney's Office.

"It appears the victim died at another location and was brought to the location after death," Wells said.

More than 20 investigators with the Major Case Squad were working Saturday afternoon out of the Bethalto Police Department. The squad's phone numbers are 377-1072 and 377-5266. The number for an anonymous tip line is 296-3000.