UPDATED 11/07/11 9:17 a.m.

CHICAGO (CBS) — A 15-year-old boy is being held without bond on charges that he shot and killed his grandmother, a Chicago Police officer, who had adopted him.

Keshawn Perkins, 15, was charged as an adult with one count of first-degree murder and one count of armed robbery in the death of Scott, 55, who was killed in her home Friday afternoon in the 8800 block of South Wallace Street, authorities said.

In court Sunday, a judge ordered him held without bond.

Prosecutors said Perkins had skipped school Friday and fell asleep while watching television in the basement. Scott found him sleeping, woke him up and began yelling at him.

He admitted to police that he struck her repeatedly about the head with a lamp and stabbed her several times with a kitchen knife “until she shut up,” prosecutors said.

Perkins then wrapped her in a blanket and dragged her to a catch basin in the back yard and dumped her there before taking her purse, which was covered with blood, and fleeing.

A 911 call was made when the front door to her home was seen open and when police got to the scene, neighbors brought Perkins to them, prosecutors said.

Two bloody knives were recovered from the basement, and Perkins, who was Scott’s adopted grandson, told police where her body was and where he disposed of his bloody clothing, prosecutors said.

Scott was pronounced dead at her home at 4:25 p.m. Friday, the medical examiner’s office said. A Saturday autopsy determined she died of multiple injuries from an assault and her death was ruled a homicide.

Scott was off-duty at the time and shared her home with several grandchildren.

A police source said the victim served as a police officer for 25 years.

“Hester would give you anything, but she’s not going to be taken advantage of,” the victim’s brother, David Scott, told CBS 2’s Mike Parker. “She put everything she had into her grandchildren.”

The woman’s neighbor, 92-year-old Wilbert Grant, said the victim moved to the neighborhood about 15 to 20 years ago and lived in the home with her grandchildren because her daughter was “having problems.”

“I’m very surprised,” Grant said. “She was a very nice lady.”

If convicted, Perkins faces a minimum life sentence because the murdered victim was a Chicago police officer.

The Sun-Times Media Wire contributed to this report.