Investigators say the victim, 59-year-old Gerry Hill, is a panhandler in the area who is known to become aggressive.
Police say he entered the Royal Deli and Grill on Knickerbocker Avenue in Bushwick around 7 p.m. Monday and got into an argument with two workers.
One of those workers grabbed a baton and hit Hill in the head.
Hill went home but later lost consciousness and was taken to the hospital where he died.
Isaiah Arocho says he was inside the store when he witnessed the first of two fights between Hill and the employees.
"It was over a credit because he owed the store some money and he was paying back and he kept asking for stuff," Arocho said. "So he got mad that they wouldn't give him the stuff he paid for so he just chucked it at the employees. The employees got mad and retaliated and they started fighting."
Arocho said Hill left, walked around the corner and down the block to his home before returning to the bodega and starting the fight all over again.
"He tried to go behind the counter and he slugged one of the workers and knocked him out, when his coworker saw him knocked out on the ground, he took an object and hit him over the head," said Fernando Mateo with United Bodegas of America.
United Bodegas of America called the 38-year-old employee's actions self-defense.
The Brooklyn District Attorney's Office says Hill had 26 prior arrests, spanning decades. They include assault, robbery, burglary, criminal possession of a weapon and of a controlled substance.
"His character has always been he's mean, he doesn't help, he thinks the world owes him something," Arocho said.
Detectives have interviewed the bodega workers and are awaiting autopsy results.
So far the workers have not been charged.
Leaders with United Bodegas of America say they will start installing 500 panic buttons in the most troubled stores throughout New York City in the coming weeks.
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