By Audrina Bigos

(CBS) – A warning about a group of kids deemed the “Teen Mob.”

A Chicago nail salon owner says they’re taking things to another level, pepper-spraying employees before leaving without paying.

CBS 2’s Audrina Bigos reports.

In the Loop at Fashion Nails, there are always people coming and going.

“Twenty years in this career and I’ve never had something happen like that,” co-owner Anh Tran says.

“It was shocking because they travel in groups and you can’t catch them,” co-owner Yen Nguyen says.

She says a “teen mob” of about nine teens came in Wednesday to get their nails done. They ran out before paying.

“If  it happens and they run off, it’s ok, but now, they’re taking it to another level,” Nguyen says.

Two guys with the group  pulled out pepper spray and sprayed two nail technicians.

Chicago police say the teens were ages 15 to 17. At least two males were in the group.