SPRINGFIELD, Mass. (AP) — A Springfield man severely injured when he was punched in the head while intervening in a dispute over a dog has died, and the man alleged to have struck him is expected to face a murder charge.

Authorities say 45-year-old Paul Bagge died at Baystate Medical Center after he was punched Tuesday by Guy Wilson.

Police say a woman went to Wilson’s home to pick up a dog he had found. The woman was getting into her car when Wilson allegedly tried to stop her because he thought she was from the MSPCA. Police say Bagge intervened, but Wilson turned and punched him, knocking him to the ground.

Wilson pleaded not guilty to assault and battery on Wednesday, but a police says that charge will be upgraded to murder.

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