"It's sad. I mean, I never thought that something like that would happen," witness Elizabeth Pina said.
It happened in broad daylight, surveillance video captured part of the confrontation.
Ruben Martinez, 47, lost his life over the theft of a $30 baseball hat.
The deadly confrontation began inside Premier Fashion, the store Martinez opened on New Main Street in Yonkers with his son last month, a location they moved to after years at a nearby location.
Ruben's son, Chris, did not want to speak on camera and employees were visibly upset over the killing.
In the video, the suspect casually walks out of the store while donning the cap and then doubles back towards Martinez, at one point you can see an object being swung.
"The owner of the store was running up to the young guy with a stick and the young guy came at him, stabbing him, and then he ran off," Pina said.
"He was all dressed up in a black sweatsuit and he had a hoodie on. It was hard to tell the face," witness Alex Ramirez said.
Martinez was stabbed twice and later pronounced dead at Jacobi Hospital.
He leaves behind a wife and four sons who say they will continue to run the store.
"He was defending his store. That was his reaction, 'I'm defending my own.' It's sad the way it happened, but it happened," Pina said.
The suspect ran off, but sources say police know who they are looking for.
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