Surveillance cameras on Linder near Montrose captured the moment a dark sedan screeched into a side alley.
As a 68-year-old woman stepped into sight, two men leapt out of the car and immediately threw her to the ground. The passenger appeared to repeatedly bludgeon her with some sort of bat or baton.
Krystian Zajac said he ran outside to the woman's aide.
"One of my co-workers heard screaming, asking for help from outside," Zajac said.
They had ripped her purse from her hands as the men dragged her across the sidewalk.
"I wish I could have been there a little bit faster," Zajac said.
Zajac helped translate to police for the 68-year-old woman, who, he said, reminded him of his Polish grandmother. The newly-installed cameras at Mercedes Codreanu's fitness center captured the entire attack.
"Am I happy that we have footage? Yes, because hopefully, that can help catch them," Codreanu said.
It is part of a growing file of footage of similar attacks police are now reviewing.
The screams of two men can heard on a video from another attack Sunday night on Leavitt Street near Berteau Avenue.
2 men chased, beaten by group of robbers on North Side: VIDEO
Police said three men chased and beat two men with an object before jumping back in a dark car and speeding off.
That was one of at least six armed robberies and attacks that police are investigating. They happened across the North and Northwest sides in a span of six hours on Sunday night.
In most of the cases, police said, the victims were hit with a club-like object, including the beating and robbery of a 66-year-old woman at this Chase ATM near Addison and Elston.
Her daughter said they were speaking on the phone as the men attacked.
"It sounded like she was getting dragged out of the car, because I can hear her scream," the victim's daughter said.
Police believe the club-wielding thieves are still driving around beating and robbing people across the city.
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