Ross Sworn in as Police Commissioner

Philadelphia has a new commissioner at the helm of the country's fourth-largest police department.

Police Commissioner Richard Ross was sworn in by Mayor Jim Kenney on Tuesday in a ceremony at Central High School, his alma mater. His promotion comes a day after Kenney took over as mayor of Philadelphia.

Ross, a 26-year veteran of the force, says he's focused on improving police and community relations, and using technology like body cameras to help fight crime. He says Philadelphians and officers have to work together to make important changes.

The 51-year-old Ross replaces Charles Ramsey, a well-regarded leader who presided over a dramatic decline in homicides.

Ramsey's reputation also earned him the national spotlight: President Barack Obama appointed him to lead a task force in the wake of a fatal police shooting in Ferguson, Missouri.