A 10-year-old Indiana girl whose disappearance prompted a dayslong search by police and volunteers was found dead in a plastic trash bag stashed in a shed behind her home Wednesday, and her stepmother was arrested for allegedly killing her.

Amanda Carmack, 34, was the person who first reported her stepdaughter, Skylea Rayn Carmack, missing on Saturday night, Gas City Chief of Police Tim Eckstein told NBC News. She said Skylea may have run away.

Skylea Carmack. Gas City Police Dept.

The girl lived with her father and Carmack in Gas City, which is about 80 miles northeast of Indianapolis, said Indiana State Police Sgt. Tony Slocum.

Police appealed to the public on Sunday to help them search for Skylea. "She is believed to be in extreme danger and may require medical assistance," the Indiana State Police said in a statewide alert Sunday.

On Wednesday, the alert was canceled when Skylea's body was found in a plastic bag in the backyard shed.

Carmack was arrested for murder, neglect of a dependent resulting in death, domestic battery resulting in death, and strangulation, according to the Indiana State Police. She is being held at the Grant County Jail.

Amanda Carmack. Grant County Jail

Police said the 10-year-old was likely killed between 4:30 p.m. and 6 p.m. on Saturday. An autopsy confirmed the child's cause of death was asphyxia by strangulation and the manner of death was homicide.

The Gas City Police Department, Indiana State Police, Grant County Sheriff's Office and Gas City residents had scoured areas near Skylea's home and passed out flyers with a picture of the 5-foot-tall, 100-pound girl. The flyers said she was last seen wearing a shirt with Mario and Luigi on it and would answer to "Sky" or "Boog."

On Wednesday night, the child's friends, family and neighbors gathered to pay tribute to Skylea, lighting candles, reading poems, reciting prayers and delivering letters.