A mother was charged with two counts of murder in the beating deaths of her two sons. Police say Magdalena Lopez, 30, beat the boys with a 10-pound dumbbell because she believed they would be better off in heaven.

Lopez was arrested Tuesday night after police responded to her 911 call and found 9-year-old Antonio Lopez and 2-year-old Erik Lopez dead in separate rooms of their home.

A police report states the woman walked out of the house with blood stains on her clothes and bare feet as officers approached - she confessed "I had to kill them. They're in a much better place now."

An autopsy determined the boys died of massive skull fractures caused by the metal weight.

Lopez's mother-in-law, Irene Lopez, says her daughter-in-law had recently been diagnosed with bipolar disorder.

Lopez says, "She'd been sick for a good six months. We took her to specialists. She was hospitalized once. We thought she was doing better, but she fooled us. Only God knows why this happened."

Lopez is being held at the Lake County Jail without bond.