Following the stabbing death of Oklahoma State Labor Commissioner Mark Costello on Sunday, U.S. Rep. Tom Cole (R-OK) offered his condolences, and discussed the loss suffered by his friends, family and community.

“I am stunned and saddened by the tragic loss of Mark Costello,” Cole said. “Mark’s death leaves a hole in the heart of our community. He was a proud Oklahoman, dedicated public servant, devoted husband and father, and a dear friend to countless others.”

Costello was involved in an altercation with his son, Christian Costello, at an Oklahoma City restaurant Sunday night, during which Christian stabbed his father repeatedly, killing him. The commissioner’s wife, the attacker’s mother, attempted to stop the attack.

“During this difficult time for his family, I pray that the Lord’s comfort will be near to their hearts and that the support and prayers of their friends will be overwhelmingly felt,” Cole said. 

Police have yet to say what may have caused the altercation that led to the attack.

The attack began inside a Braum’s grill and ice cream shop, and continued outside with Christian allegedly stabbing his father in the head. A witness eventually hit Christian with his car to stop the attack

The younger Costello is in the Oklahoma County jail, awaiting formal charges by prosecutors.

His family has since released a statement stating that he suffers from mental illness.