Forty-seven-year-old Matthew Reiss, of Upper Hanover Twp., Montgomery County, was arrested in May after investigators say they found 10 images of child porn in his email.
The images depicted "children under the age of 13 in various stages of undress, in sexual poses and being sexually assaulted," the D.A.'s office said.
On Friday, the office of District Attorney Kevin Steele said a search warrant revealed more child pornography images.
Reiss, an 18-year veteran of the Hilltown Township Police Department in Bucks County, is now charged with 1,700 felony counts of possessing child pornography.
Since his arrest, the Hilltown Township Police Department has placed Reiss on administrative leave.
Action News interviewed Reiss in July 2020 after his bodycam footage recorded the officer and his partner rescuing a horse from a barn fire in Hilltown Township.