A Bridgeview woman sorting donated clothes at a Chicago thrift store was shot and killed when a gun hidden in a sock accidentally fired.

Carmen Dominguez, 54, and a man were sorting items at Unique Thrift Store, 9341 S. Ashland Ave. in Chicago, at about 9:40 a.m. Friday when her co-worker found a 22.-caliber handgun inside the sock, reports DNAInfo.com. The gun slipped out of the sock and went off, striking Dominguez in the chest. Dominguez was pronounced dead at Advocate Christ Medical Center in Oak Lawn at 10:47 a.m., according to the Cook County Medical Examiner's Office. Police are treating this as an accidental shooting, but the U.S. Labor Department sent agents to the store to investigate, the news site reported.

"Preliminary indications during the course of the investigation are that this is a tragic, accidental incident," police said in the statement to the Chicago Tribune. Her husband, Victor Campos, told DNAInfo.com his wife worked for Unique Thrift for almost 25 years and she would sometimes complain about working conditions there. He returned to the store with police to retrieve his wife's jacket.