Chitwood said the 40-year-old mother of three fought back by kicking Knapp in the groin, but "in a fit of rage, he kicks her in the head and face."
"She couldn't breathe," Chitwood said. "She thought she was going to die. At one point, he bit her on the nose. You can't even recognize her face. That's how brutally she was beaten."
Knapp, 38, took $300 from the woman's dresser drawer and fled the house on Snowden Road near Patterson Avenue. The woman was treated at Delaware County Memorial Hospital, where she reported deafness in one ear and difficulty swallowing. Chitwood said she may need reconstructive surgery.
"He's a dangerous, dangerous individual," he said of Knapp, who has been arrested before on charges of assault and stalking. "We deal with domestic violence every day, but the beating she took, she was probably as close to death as one could get."
Anyone with information on Knapp's whereabouts is asked to call Upper Darby police at 610-734-7677.