An Indianapolis man who broke up a fight between his pit bull and a neighbor’s Doberman was in critical condition Monday.

Timothy Niemeyer, 56, was at Wishard Memorial Hospital after he suffered an apparent heart attack while breaking up the dog fight in the 500 block of North Oakland Avenue on Sunday afternoon, police and hospital spokesmen said.

Indianapolis Metropolitan Police Department officers responded to a dog-attack call just before 2 p.m. and found Niemeyer in medical distress, according to a news release from IMPD Sgt. Matthew Mount.

Niemeyer’s pit bull had broken its chain and was fighting with a neighbor’s dog. Both dogs were injured, Mount said, but no people were bitten.

Animal control officers confiscated the pit bull; the Doberman was returned to its owners.