Stepson, 21, charged with stabbing off-duty Chicago officer, police say

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CHICAGO — A man is charged with stabbing an off-duty Chicago police officer, who is reportedly also his stepmother, while she was driving.

David Johnson, 21, surrendered to police just a few hours after the Friday morning attack in the South Shore neighborhood.

The 47-year-old woman was driving Johnson to a therapist for behavioral issues. He was recently diagnosed with schizophrenia.

Police say, when she stopped the car at 76th and Stony Island, Johnson stabbed her with a kitchen knife.

Her car then crashed into a school bus.

She was treated and released from the hospital on Sunday.

Johnson was denied bail.