A civilian official of the New York City Police Department's pension fund has been charged with taking computer data that could be used to steal the identities of 80,000 current and retired cops, sources said.

Anthony Bonelli allegedly got into a secret backup-data warehouse in the borough of Staten Island last month and walked out with eight tapes packed with Social Security numbers, direct-deposit information for bank accounts, and other sensitive material.

The Police Department's pension fund planned to send out letters Wednesday to the 80,000 potential victims, warning them of what happened and offering help if their identities were stolen.

Bonelli, 46, served as the fund's director of communications, but didn't have authorized access to the site, at an undisclosed Staten Island location, where the backup data was kept on VHS-like tapes.

Sources said he managed to get past a guard on Feb. 21, unplugged video cameras, and left with the stolen tapes.