Kenneth Cost is retiring as chief of the Mesa Police Department effective June 30.

Cost has served 30 years with the department, leading the agency since 2019.

"Chief Cost has been instrumental in transforming the Mesa Police Department into a model law enforcement agency," Mesa City Manager Chris Brady said.

"Under his leadership, Mesa has seen dramatic reductions in violent crime, unprecedented solve rates and stronger community partnerships. He set a new standard for policing in Mesa and across the nation through strategic planning, officer training and technological innovation."

Under Cost, more than 300 officers were hired, “reducing vacancy rates to historic lows,” according to a city release. In addition, a fifth police station has been added and renovations begun at Mesa police headquarters.

Some programs implemented include a jiu-jitsu program that officials said has reduced use-of-force incidents in Mesa, the SPARC Youth Sports Program, training reforms, drone first responders and a Real-Time Crime Center, the release stated.

"It has been the greatest honor of my professional life to serve as Mesa’s police chief and to work alongside the dedicated men and women of this department," Cost said.

“Together, we've built a department that prioritizes community engagement, officer wellness and innovative approaches to public safety. I'm deeply proud of what we've accomplished, and I know the foundation we've laid will continue to serve the Mesa community for years to come."

A new Mesa police chief will be appointed in June by incoming City Manager Scott Butler, officials said.