Updated 01/22/14 - 2:58 p.m.
MUNDELEIN, Ill. (CBS) -- An 11-year-old girl was killed at her home in far north suburban Mundelein on Tuesday, when she was stabbed 40 times. Her 14-year-old half-sister has been charged with the murder.
Lake County Medical Examiner Tom Rudd said the 11-year-old girl suffered 30 stab wounds to her neck, chest and arms; three slash wounds to her face; four defensive wounds to her left hand, and a defensive wound to her left thumb. In all, Rudd said she was stabbed 40 times. Two of those wounds punctured her left lung.
14-Year-Old Charged With Murdering Half-Sisterd
She also suffered bruises to her chest, and non-penetrating knife wounds "too numerous to count," meaning she probably was jumping away from the knife.
A 14-year-old girl has been charged with three counts of murder after appearing before a juvenile court judge on Wednesday.
Mundelein Police Chief Eric Guenther said police received a 911 call from the 14-year-old girl around 8:30 a.m. Tuesday, from home in the 1600 block of Woodhaven Court. When officers arrived, they found the 11-year-old girl dead in a bedroom of the home.
Guenther said the two girls were the only people present at the home at the time. The victim's parents were notified of her death early Tuesday evening.
"As I'm sure you can understand, it was very difficult news to deliver, and for them to hear. So they are coping in the way that they know to cope, and are with their family now," he said.
"We are very confident that this is an isolated incident, and that there are no other concerns to the neighbors and/or the community," he said.
Lake County State's Attorney Michael Nerheim said a decision has not yet been made whether prosecutors would seek to have the girl charged as an adult. He said that decision might take a few weeks, so prosecutors can review police reports and other evidence.
The 14-year-old first told police there had been a home invasion, prompting a brief lockdown for three local schools, but she later changed her story.
According to prosecutors, she later recanted her story and confessed to making the home-invasion story up. The 14-year-old told police she was upset by being hit by her half-sister the night before. The 14-year-old also told police her half-sister wasn't thankful for all the things she did for her.
Guenther said the lockdown was only a precaution, and lasted only about 15 minutes, when police determined there was no danger to students.
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