This story contains descriptions of graphic content.

(CNN) The families thought they were donating the bodies of their loved ones to a company that would send them to medical researchers to help find cures for diseases like Alzheimer's and Parkinson's.

But when federal authorities raided the Arizona facility of the Biological Resource Center in January 2014, they made a horrific discovery: bodies piled atop one another, buckets full of body parts and other unsettling scenes, details that came to light recently when a former FBI agent gave a statement for a lawsuit.

Thirty-five relatives of people whose bodies were supposed to be donated for science research between 2010 and 2014 have sued officials who worked at Biological Resource Center in Maricopa County or its facility in Illinois.

The grim discoveries were detailed in a civil lawsuit which was first filed in 2015, has been amended several times and is headed for trial this fall in a Phoenix court. It alleges officials deceived relatives who donated the remains of their loved ones and the company conspired to traffic bodies and body parts for profit.

A raid unveils body parts

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