By Jessica Vallejo

MIAMI (CBSMiami) – A family is in mourning after a Miami business owner was fatally shot during a robbery just moments after closing up his store.

Walter Castaneda Jr. said his father’s life was taken over money.

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“It’s hard to believe he won’t be home anymore. It is really hard for me,” he said. ” He was just about to turn 65. He was just about to retire. He had a heart of gold.”

Castaneda said his father, Walter Castaneda Sr., had owned the Boost Mobile store at 12th Avenue and 5th Street for years. He said his father was targeted in the Friday night attack because he likely had a large amount of cash on him.

“When he locked the front, an individual came with the gun and asked him for his money. They argued and it seems like the guy shot my dad first,” said Castaneda.

He said surveillance video shows his father fall to the ground as he tried to defend himself.

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“They exchanged fire together. The man jumped in the car and more shots were fired from there. The guy took his money and his life,” said Castaneda.

Castaneda Sr. was taken to a nearby hospital but didn’t survive his injuries.

His son hopes the police find the person responsible.

“I just don’t understand how someone can just destroy someone’s life,” said Castaneda.

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Anyone with information about the fatal robbery is urged to contact the police.

Jessica Vallejo