FEDS RAID SUBURBAN CREMATORIUM, MEDICAL RESEARCH OFFICE - The 2015 Search for Jimmy Hoffa

SCHILLER PARK, Ill. (WLS) -- Federal agents raided two suburban business connected to scientific research of human bodies.

The FBI is not offering many details, but said their presence at a Schiller Park crematorium on Tuesday is connected to an ongoing criminal investigation.

FBI agents were also seen executing a search warrant and removing several boxes of evidence at a second location, a Rosemont office building. The Biological Resource Center of Illinois - a body donation center, according to its website - is located on the fifth floor of that building. Families can donate their late relatives' remains to the company for the purposes of medical research.

The owner of the Biological Resource Center of Illinois also owns this Schiller Park crematorium, a company called Cremation Service Inc. FBI agents and CDC officials were seen here on Tuesday, according to others who work in this office complex.

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