A Pennsylvania man out for a walk with his fiancée and their dog died after getting punched in a local park, police said.

Drew Justice, 38, and his fiancée, Kristi Buchholz, were walking their Shih Tzu in Philadelphia’s Gold Star Park on Saturday evening when they encountered a man with a dog that was off its leash, witnesses told the Philadelphia Inquirer.

Justice asked the man to leash his dog. The man became outraged and punched Justice in the face before fleeing, onlookers told NBC10. Justice fell back and hit his head on the pavement, witnesses recalled.

Witnesses heard the commotion and called the police. Medical staff at Jefferson University Hospital pronounced Justice dead at 9:51 p.m.

“I heard the screaming,” Justice’s neighbor, Julie Abruzzese, told NBC10. “But it was already done. He was laying on the ground.”

“Him and his fiancée were ready to get married,” Abruzzese added. “It’s heartbreaking.”

Abruzzese said both dogs and children frequent the park, and there’s been some recent tension over safety issues.

“They’re going to tell you their dog’s friendly,” Abruzzese said. “You don’t know at that moment if a dog’s going to turn. I’ve always said that one day they’re going to bite these children. But here it turned out somebody got killed over a leash.”

The Philadelphia Medical Examiner’s Office said Justice died from “blunt impact trauma injury to the head” and ruled his death a homicide, according to the Inquirer.

Justice, who worked as a data management programmer, was a valued member of his community.

“He raked leaves at cleanup days, hung lights for our winter celebration and was always up for firing up the grill to feed volunteers or raise money for the park,” Regan Cooper, chair of the Friends of Gold Star Park group, told the Philadelphia Inquirer.

Police did not identify a suspect and no arrests were made, police said. Police describe the suspect as an “unknown white male wearing dark clothing.”