Police said the group of four male suspects and three female suspects spray-painted "The Bean" and left the iconic sculpture tagged with gang graffiti. Investigators said they showed up overnight to Millennium Park armed with cans of spray paint and started vandalizing.
First, police said the group targeted "The Bean" sculpture, covering the artwork in spray paint. Then the suspects sprayed graffiti on the Cancer Survivor Wall and several park benches and trash cans at Maggie Daley Park.
The vandalism occurred just before the big July 4th weekend, where thousands of people will head to Chicago and to Millennium Park for the big fireworks display.
WATCH: Below video shows what it takes to clean the Bean
The Department of Cultural Affairs and Special Events released a statement saying, "Last night's vandalism to Chicago's iconic 'Cloud Gate' is reprehensible. Crews are in the process of removing the graffiti."
The sculpture cost millions of dollars to build and has been part of Millennium Park for 15 years. "The Bean" is made from 168 steel plates. Fabrication started in 2002 and took more than two years to complete.
The stainless-steel skin was attached to the internal structure of "The Bean." That lets it expand and contract during Chicago's extreme weather shifts.