Police in Illinois say that the ex-boyfriend of an Arlington Heights woman who returned from vacation to find her home burglarized and pet dog dead in the oven is now is a “person of interest” in the investigation.

Authorities first interviewed the ex-boyfriend, 29, on July 5, one day after the woman and her two children made the gruesome discovery. The woman thought someone had stolen the dog -- a Cavachon named Coco -- only to have her 9-year-old daughter encounter the family pet inside the oven.

Police released the ex-boyfriend on July 7 after investigators determined that there was insufficient evidence to file charges against him, Police Sgt. Rick Kappelman said Friday, according to the Daily Herald.

The woman also reported approximately $3,000 worth of jewelry stolen.

Police believe the incident occurred sometime between about 11 p.m. on July 3 and early July 4, according to CBS Chicago.

As of Friday there were no other suspects in the case.