Police say thieves hit at least five locations since last week. The robberies happened on the city's North Side and West Side.
The robbery spree included Thursday morning's incident at Griddle 24 in River North. Masked men with guns stormed the 24-hour diner, taking items from customers while they were eating.
ABC7 also obtained new video capturing another one of the robberies in progress at Arturo's Tacos in Bucktown.
This is only the second time Arturo's Tacos has either been robbed at gunpoint or an attempted robbery happened since the restaurant opened nearly 40 years ago. This recent one, police say, made it part of an armed crime spree spanning days.
"We are concerned about the safety of our employees," Arturo's Tacos general manager Arturo Torres said.
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.
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