Advertising agency Ackerman McQueen is asking a judge to block a fired employee from turning over "stolen" records to the National Rifle Association.

The Oklahoma City-based ad agency and the NRA split this year after 38 years and are now in a bitter legal fight that is playing out in courts across the country. Their dispute comes at a time when the NRA, the longtime gun rights champion, is coming under increasing scrutiny in the wake of mass shootings.

The former employee, Tammy Payne, is scheduled to speak to NRA attorneys on Jan. 3 in Oklahoma City. She has been told to bring with her a number of records pursuant to a subpoena issued in the case in Virginia.

On Thursday, Ackerman McQueen asked an Oklahoma County district judge to quash the subpoena for records "for several reasons." The advertising agency described Payne in a legal filing as "a disgruntled former employee" who violated her employment agreement "when she stole confidential documents ... and continued to retain the same."