Identity theft thieves profit from stolen medical files at a Northwestern University medical practice

Seven suspects have been arrested in an identity theft case at Chicago's Northwestern University. Three other individuals are wanted on felony arrest warrants, according to a statement released by the Cook County Sheriff's office on Tuesday.

In what is described as a "sophisticated identity-theft ring," a janitor stole data from as many as 250 patient files at a Northwestern University medical practice and, with the help of her two sisters and friends, used the personal information to charge more than $300,000 in jewelry, furniture, appliances and electronics. The thieves then sold the illegally obtained merchandise.

According to the Cook County Sheriff's office, the theft began with a janitor at Millard Cleaning Service, working the night shift, who  stole personal information from patient files at the Northwestern Medical Faculty Foundation's offices and passed it to others, who then used the information illegally.

In some cases, the identity thieves opened credit accounts in the victim's name – both in person and at online retailers. In other cases, they simply added their names to victims' accounts. They then often went on an immediate shopping spree -- sometimes charging in excess of $5,000 at a time.

The ring was busted as a result of "Operation Quick Charge," a five-month investigation headed by the sheriff's financial crimes unit with assistance from the U.S. Postal Inspection Service and Chicago and multiple suburban police departments. The break in the case came when investigators noticed that the majority of the victims saw doctors on the same two floors of the facility and narrowed the search down to the janitor assigned to those floors.