Bestselling Mystery Author Guilty of Possessing Child Sex Abuse Materials

New York Times-bestselling mystery author Brendan DuBois has pleaded guilty to possessing sexual child abuse materials.

The author was sentenced to 3 1/2 to seven years in prison, the Associated Press reports.

DuBois reportedly possessed more than 5,600 images on his computer that had been flagged as “possible child abuse content,” according to SeaCoastOnline.

Twenty of those images were described in an affidavit filed by police in Exeter, N.H., per SeaCoast Online. “I estimate the age of the above-mentioned children to be between infancy to 12 years old,” Detective Bailey Teixeira wrote in the affidavit, according to SeaCoastOnline.

Detective Teixeira also looked into DuBois’ online search history, where he found articles about people arrested on child pornography charges, as well as searches including “How to tell if Google has reported me to the police” and “I accidentally saved child pornography to my main Google Drive,” per SeaCoastOnline.

The author was arrested in Exeter last summer, and has been in jail ever since, the AP reports. On Thursday, DuBois appeared in court, where prosecutors agreed to drop two of the six possession counts against him as part of a plea agreement, per ABC News.

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DuBois is the author of more than 25 novels, including co-written with the prolific, hugely popular author James Patterson.

DuBois must now register as a sex offender. One of the publishing houses he’s worked with, Severn River Publishing, announced it would be taking his books off their website.

PEOPLE reached out to DuBois’ lawyer for comment but did not immediately hear back.