CHICAGO (CBS) — The investigation into identity theft at a supermarket in north suburban Wilmette continues to expand.

Wilmette Police Chief Brian King told WBBM Newsradio that detectives have collected information from more than 50 victims, all of whom used their credit cards at Treasure Island Foods’ Ridge Road store.

READ MORE: Nearly 17,000 Unemployment Claims Filed In Illinois Last Week Amid COVID-19 Pandemic

Police have handed off that information to the U.S. Secret Service, which is making progress in the case.

READ MORE: 'Baby Whisperer' Patti Ideran Has Some Advice For How To Calm Fussy Or Colicky Babies

King told Newsradio the crime is typically under-reported, and not all insurance companies require it, but he continues to ask victims to come forward.

Treasure Island has issued a statement that says it is cooperating fully with authorities in what it says appears to be an international hacking conspiracy.

MORE NEWS: Mother, 2-Year-Old Daughter Carjacked In Wicker Park

The credit card information that was stolen has been used as far away as South Africa.