The Bergen County Prosecutor's Office accused a Hackensack Police Officer of tampering with its investigation into an alleged assault committed by fellow Hackensack Police Officer Anthony Ferraioli.

Alberto H. Gutierrez, 57, is charged with tampering with witnesses and obstruction, Prosecutor John Molinelli said Thursday. Gutierrez, a Hackensack resident, was among several Hackensack Police Officers and two Paramus Police Officers who were questioning Andrew Milberg at his Hackensack home on June 7. The visit was part of an investigation into an at in Paramus earlier that day, Molinelli said.

During the questioning, and filed a false police report afterward, Molinelli said. The incident prompted a Bergen County Prosecutor's Office investigation. Molinelli said that Gutierrez, after learning that the Prosecutor's Office was interviewing witnesses, began contacting those witnesses and pressuring them into telling him about the investigation.