(CNN) — An Indiana man convicted in the death of his 11-week-old son was punched in the face after being sentenced on Wednesday.

Autopsy results showed that the baby had died from blunt force trauma to the head.

Kwin Boes had been sentenced to 20 years in prison for the child’s death when the baby’s uncle Matt Harley ran through the hallway to deliver a punch to the face.

The encounter was captured on video. Harley is now facing a battery charge.

Officers ushered Boes quickly out of the area.