The cop who stealthily recorded 100 hours of his former chief talking -- and using racial slurs -- had remained anonymous, until yesterday.

A filing in the federal racial assault case against former Bordentown Township Police Chief Frank Nucera Jr. names the person who handed over the recordings to the FBI as Nathan Roohr, a patrol sergeant.

His name appears in an FBI report attached as an exhibit. Two agents report that they met with Roohr and received the recordings.

Federal prosecutors said Nucera can be heard in the recordings using the N-word to describe African Americans, and at one point saying they were "like ISIS, they have no value. They should line them all up and mow 'em down."

The then-chief's comments are described in a complaint charging Nucera with a federal hate crime and related charges for the alleged beating of a handcuffed Trenton teenager in 2016.

Nucera's attorney, Rocco C. Cipparone Jr., filed the motion Thursday that named Roohr. It was a request to allow more time for pretrial motions and to fully review the hours of recordings, some of which are difficult to hear.

He also references a part of the FBI document which says Roohr deleted some of his recordings that he determined contained "nothing of importance." Cipparone argues that the deletion of some recordings could impact Nucera's right to a fair trial.

Roohr was promoted to Sergeant in August 2015. He did not return an email requesting comment Friday.

Nucera is free on bail after he was indicted in late 2017 on the charges of hate crime assault, deprivation of civil rights under the color of law and making false statements.

With Thursday's filing, one of many continuances requested in the case, the parties now have until July 16 to submit pretrial motions.

Joe Brandt can be reached at jbrandt@njadvancemedia.com. Follow him on Twitter @JBrandt_NJ. Find NJ.com on Facebook.

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