St. Charles County Prosecuting Attorney Tim Lohmar says he plans to seek the death penalty in the killing of a woman in O'Fallon.

Lohmar announced Thursday that investigators have found aggravating circumstances that warrant asking a jury to consider the death penalty against 63-year-old Terry Glennon Culberson.

Culberson is charged with first-degree murder in the February death of his ex-girlfriend, 55-year-old Dorothy Hall. Her body was found in Culberson's home with several gunshot wounds to the head.

Culberson fled after the shooting but he was captured in Oklahoma about 10 days later. He remains in custody on a $500,000 cash-only bail. A trial date has not been set.

The St. Louis Post-Dispatchreports that Culberson was previously convicted of assault with intent to kill with malice.