CHICAGO (WLS) — Chicago authorities have issued a warning about a string of robberies targeting local restaurants.

According to police, a group of thieves has struck at least five different establishments over the past week. These incidents have occurred across the city’s North Side and West Side neighborhoods.

ABC7 Chicago is now streaming 24/7. Click here to watch

One robbery took place on Thursday morning at Griddle 24, a popular 24-hour diner in River North. Witnesses reported that armed, masked men entered the diner and stole valuables from patrons who were in the middle of their meals.

ABC7 has acquired footage of another robbery in progress at Arturo’s Tacos in Bucktown, shedding light on the bold tactics of the criminals.

This incident marks only the second time in nearly four decades that Arturo’s Tacos has faced an armed robbery or attempted robbery, according to police. This occurrence is part of a broader crime spree involving armed thefts that have unfolded over several days.

“The safety of our employees is a major concern for us,” stated Arturo Torres, the general manager of Arturo’s Tacos.

While it was back to business at Arturo’s Tacos Friday, the feeling of fear still simmered beneath the staff trying to make an honest living after guns were pointed at their faces days ago.

“It was about 60% full that night when they came in,” Torres said. “They just walked straight up to the register. They asked the cashier for money, but I don’t know what scared them off.”

Security video shows the brazen robbery attempt overnight Sunday morning while the restaurant was packed. At least two suspects could be seen wearing ski masks and rushing in with guns drawn.

The suspects then ran out empty-handed within seconds. Police say they left in a stolen car.

“She went to the door, and she locked it,” Torres said.

Customers were then seen ducking under tables for safety.

“I don’t know if they’re going to want to come back, because now they see it’s crime in the area,” Torres said. “So, it affects us. It affects our living.”

ABC7 spoke to the restaurant’s general manager three years ago when his family-owned restaurant was robbed for the first time since it opened in 1988.

“This is something that’s new to us, and I think, it’s more prevalent now in the area,” Torres said. “I heard that 7-Eleven right here on Damen had also gotten robbed. “

Chicago Police confirmed that, saying the masked offenders are part of a crew of about two to three people.

Investigators said the group is behind at least five armed robberies and attempted armed robberies at mostly late-night businesses across the city, and at least one carjacking, spanning from Sunday to Thursday.

The crime spree included Griddle 24 in River North. The manager there said employees and patrons were robbed early Thursday morning, and one of their workers was pistol-whipped.

So far, police say no one has been arrested.

INTERACTIVE SAFETY TRACKER Track crime and safety in your neighborhood