CHICAGO (CBS) — Police in west suburban Cicero are looking for a group of men who broke into a gold exchange store and attacked an employee, while filling up a bag with piece after piece of expensive jewelry.

CBS 2’s Marissa Bailey reports a 110-pound French Mastiff scared the suspects off.

Roosevelt Gold Exchange at 1203 S. Cicero Av. in Cicero was the target of an armed robbery Monday afternoon, but the suspects picked the wrong store to hold up.

Surveillance video shows a white minivan parking in a lot next door.

Three suspects stood at the window distracting the clerk, while a fourth used a crowbar to open the office door, and a fifth waited in the van outside.

The clerk was tied up and then hit with the crowbar. One of the suspects filled a bag with more than $40,000 in jewelry.

“It looks like a movie from Hollywood, where the next thing they do is they shoot him,” said store owner Louie Rainone.

The robbers covered the clerk’s head with a pillowcase, wrapped with a phone cord.

The suspects are later seen on tape leaving after being in the store for 11 minutes, because they came across Rainone’s 110-pound French Mastiff, Max, who was in the back room when the suspects came in to cover their tracks and steal video surveillance tapes.

“They went to go in the back, and I have a 110-pound French Mastiff, and the dog went at ‘em,” Rainone said.

Max proved to be the unintended security system that Rainone hopes will help police get the guys who robbed his store.

“Every dog has their day. Yesterday was Max’s. Tomorrow it will be their day,” Rainone said.

The clerk is fine — a little shaken up, but expected to be okay.

The robbers left behind a Mike Ditka rookie card in the safe.

Police are looking for the public’s help to track down the robbers. If you know anything, you’re asked to call Cicero police at 708-652-2130.

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