Dallas police officials have confirmed that police Chief U. Renee Hall is on medical leave following surgery earlier this week.
An internal email obtained by The Dallas Morning News shows Hall began her leave July 10, but the department didn't publicly acknowledge her departure until a week later.
Police spokesman DeMarquis Black said Friday that it's not clear when she will return to work.
A police statement says Hall underwent a wellness check in January and doctors "expressed concerns that needed to be addressed," leading to what was described as "major surgery." The statement says she's resting comfortably at home.
Executive Assistant Chief David Pughes is the acting chief until she returns.
Hall is in her second year as police chief after previously serving as deputy police chief in Detroit .