A 47-year-old New Jersey state trooper was arrested Thursday and charged with possessing child pornography, prosecutors said.

Jefrrey G. Reitz, of Williamstown, was being held pending a court appearance on third-degree possession of child pornography. Reitz, who was assigned to the Commercial Carrier Safety Inspection Unit, has been suspended by the New Jersey State Police.

“Jeff Reitz is not guilty and we will work through his exoneration and restoration to duty,” his lawyer, Stuart J. Alterman, said in an email.

Reitz allegedly engaged in an exchange of sexually explicit email with an adult woman in December 2014 when she proposed that he sexually assault her 5-year-old daughter. “ANY PICS?” he asked.

The woman sent him a picture of the child’s genitals and Reitz allegedly replied: “NICE!” Prosecutors said Reitz also sent the woman pictures of his genitals.

The email exchange was discovered later during an investigation of the woman, who is serving a seven-year prison sentence for permitting a child to engage in pornography.