DALLAS (AP) — Dallas police say all cases assigned to an assault detective are under review after a number of cases weren’t handled properly and had “no documented investigative follow-up.”

A department statement Wednesday didn’t specify the number of cases under review, but said the department discovered during an audit that “a number” of cases hadn’t been handled properly or cleared in the agency’s internal reporting system.

A department spokesman says the detective worked in a unit that investigates shootings and other types of assaults. The detective, who wasn’t identified, had been assigned the unit since January 2015.

An internal investigation is underway, and the detective has been placed on restrictive duty and isn’t being assigned any new cases while reviewing past cases with a supervisor.