ST. CHARLES, Mo. —  An eastern Missouri man shot his own 12-day-old son with a BB gun, police said.

Shawn Michael Mohan, 20, of St. Charles County, shot the baby several times, causing circular-shaped bruises to the face, left arm, hand, foot, hip and buttocks, police told the St. Louis Post-Dispatch in Wednesday's edition. The injuries were not life-threatening.

"He's claiming it was an accident, but we feel that the evidence points otherwise," said Lt. Craig McGuire of the county Sheriff's Department.

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The injuries were discovered when the child was taken for a routine exam at his pediatrician's office. The doctor called the Missouri Division of Family Services.

Police believe the shooting happened Dec. 21 at Mohan's apartment near St. Peters.

Mohan is on probation after pleading guilty in July 2005 to child endangerment, related to a serious head injury to Mohan's first son when the boy was 3 months old. He pleaded guilty and was given a five-year suspended sentence.

On the new charge, Mohan was being held at the St. Charles County Jail on $100,000 cash-only bond.