CHICAGO (CBS) — Nick Viverito watched his best friend die this weekend, when his friend’s throat was slashed during a weekend trip to watch the Chicago Bears play in Florida.

Police said Matthew Hinson, 27, cut William Christopher Pettry’s throat in a fit of jealous rage early Sunday inside Fioon MacCool’s Irish Pub in Jacksonville when he saw Pettry talking to his wife.

CBS 2’s Brad Edwards spoke with Viverito about what happened just hours before they were supposed to watch the Bears play the Jacksonville Jaguars.

“I’m stunned. My friend gets up to the bathroom, and get a round of drinks, and he’s dead,” Viverito said.

He saw Pettry die.

Viverito was Pettry’s best man, and godfather to his first child.

Pettry, a Lake Villa husband and father, worked a lot, according to Viverito.

“He works his ass off to support his family,” Viverito said.

Last weekend, at Viverito’s urging, the two Bears fans went to Jacksonville to see the Bears.

At a local restaurant, the two made friends with a vacationing couple.

“Any time I spent with him was great,” Viverito said.

So how did Pettry end up dead? Authorities said Hinson simply walked up to him, slashed his throat, and walked away.

“For some reason, he became jealous, enraged, whatever you want to call it, and approached our victim,” said Jacksonville Sheriff’s Lt. Rob Schoonover. “According to one of the eyewitnesses, he calmly and basically cold-blooded just cut the victim’s throat, and calmly walked out of the restaurant.”

But Viverito said there was no reason for Hinson to be jealous of Pettry, much less kill him out of anger.

Viverito said the only contact he and Pettry had with Hinson’s wife was offering her a seat at their table, because the couple had nowhere to sit.

“Nothing makes sense,” Viverito said.

After returning home, Viverito said he was cleaning out his voice mail, and found an old message from Pettry.

“When I think about him … it really hurts, but … I gotta think about his family, and what we can do for his family now,” he said.

A memorial fund has set up for Pettry’s family. You can make a donation by clicking here.

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