Former Philadelphia Police Commissioner Charles Ramsey told NBC News Sunday morning that the United States is “sitting on a powder keg” as tensions between police and communities across the nation boil over into tumultuous and sometimes violent protests.

Ramsey, who passed the helm of the Philadelphia Police Department last year, was tapped in 2014 by President Obama to lead his Task Force on 21st Century Policing. The White House established the task force to take a hard look at police-community relations in the wake of calls for more police accountability and a number of earlier killings by police that stoked controversy. FULL REPORT