A search of the Newark house of a man accused of sexually assaulting a 13-year-old led to the morbid discovery of mummified human remains and an “altar to an unknown deity,” the Essex County Prosecutor’s Office announced Friday.

Robert Frank Williams, 53, of Newark, was charged with various endangering the welfare of a child offenses, sexual assault of a victim between the ages of 13 and 15, child luring and desecration of human remains, officials said.

The Newark Police started investigating Williams after they received word that he sexually assaulted the child for several months in 2018, authorities said.

On Thursday, detectives from the prosecutor’s office and Newark Police executed a search warrant Williams’ home and found the mummified human remains in a bin in the closet and the altar in his bedroom, according to a release.

The identify of the remains was not released Friday and no other information was provided by the prosecutor’s office.

Chris Sheldon may be reached at csheldon@njadvancemedia.com. Follow him on Twitter @chrisrsheldon Find NJ.com on Facebook.

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