A woman accused in a failed murder plot prepared for the deed by filling a "murder bag" with syringes, a sledge hammer, a saw and duct tape, authorities said Tuesday.

Elizabeth Ann Tillman, 22, was arrested after police said she broke into her female neighbor's home early Monday by jimmying the lock with a library card and then fired at least seven shots from a handgun. The neighbor, Crystal Lee Walker, was hit in the leg after she and her 4-year-old son barricaded themselves in a bedroom and Tillman fired through the door, police said. The child was not hurt.

Sheriff James Metts said Tillman carried a black bag into the home and authorities later found it outside Tillman's house. Inside were two plastic syringes filled with insulin, a sledge hammer, duct tape, latex gloves, scissors, glue, a drywall saw and bullets, he said.

Investigators think Tillman wanted to inject Walker, 24, with insulin to cause her to go into a diabetic coma, Metts said.

"You don't usually hear about a murder bag," Metts said. "She was going to torture this lady and make sure she killed her."

The women had been involved in a dispute for about a year because Tillman believed Walker was being unfaithful to her boyfriend and "didn't like that," Metts said.

After Tillman broke in and started shooting, Walker and her son escaped through a bedroom window, authorities said.

Tillman bought the 9 mm handgun used in the attack last month and practiced firing the weapon at a firing range, police said.

Tillman was charged Monday with two counts of assault with intent to kill, first-degree burglary and possessing a weapon during the commission of a violent crime.