NEWTON — A 48-year-old Sussex County man pleaded guilty Thursday to sexually assaulting a 10-year-old girl and sharing the images of the incident on a peer-to-peer computer network, the county prosecutor's office said.

Christopher Bootsma, formerly of Hopatcong, pleaded guilty to first-degree aggravated sexual assault and first-degree endangering the welfare of a child.

As part of a plea bargain agreement, the prosecutor’s office will recommend a 20-year prison term with credit for time served. He will be ineligible for parole until he serves 85 percent of the sentence.

Bootsma was arrested Aug. 3, 2011, at a motel in Andover Township after police found 123 CDs and DVDs containing more than 17,000 images of child pornography • and a bandolier containing nearly 100 rounds of ammunition on a dresser in a room he rented.

A search of the room also uncovered several Nazi uniforms and Nazi military books, police said at the time.

Police found the contraband during a room-to-room search after a bomb threat was reported at the motel on Route 206.

At the time of his arrest, police said Bootsma told them he had recently lost his home in Hopatcong due to a foreclosure proceeding, and his wife and three children were staying in an apartment in Netcong. He said he was living at the motel with the family’s dog because pets were prohibited at the apartment.

The assault occurred in August 2005, the prosecutor's office said.

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