59 people were arrested, during a pre-holiday undercover dubbed “Operation Whoville” that netted grinches. They are professional shoplifters around Chicago who were part of sophisticated fencing rings, police said. Federal, local, and county authorities coordinated the sting to bust several crime rings in the act.

The grinches in these operations are known as “boosters,” or professional shoplifters. Authorities say they often go into a store with a list of items that they know they will be able to sell quickly and for a good price.

“They’re very organized. Everybody has a job to do,” said Cook County State’s Attorney Anita Alvarez in a Sunday press conference where the arrests were annonced, according to ABC News’ Chicago affiliate WLS-TV. “They know what it is, and they know exactly where the merchandise is going once they get it out of the store.”

“Operation Whoville” began in October and focused on malls in suburban Chicago and stores on the city’s famous downtown shopping street, the Magnificent Mile.

“It was a big operation and the significance was that most of the work done by police departments in regards to financial crime is reactive in nature, but this was a proactive approach,” Orland Park Police Department Chief Tim McCarthy told ABCNews.com.

Of the 59 grinches arrested included Phillip Mazurek, a Skokie, Ill., man accused of stealing a $5,000 crystal vase from a store on the Magnificent Mile.

“These things can be sophisticated,” McCarthy said. He said that thieves in one of the rings would ship the stolen goods to Miami and, from there, they’d be shipped to South America to be sold.

“It was a great effort and it’s going to continue,” McCarthy said. “These people who engage in this kind of activity aren’t going to know next time if we’re there watching. There’s hopefully going to be a Whoville Two.”