Baltimore Police Commissioner Darryl De Sousa has resigned and a national search has been launched to find his replacement, Mayor Catherine Pugh’s office announced Tuesday.

“I want to reassure all Baltimoreans that this development in no way alters our strategic efforts to reduce crime by addressing its root causes in our most neglected neighborhoods,” Pugh said in a statement. “This broad-based, grassroots approach — underpinned by the utilization of new crime-fighting technology — is working and will continue to be effective as indicated by the downward trend in violence.”

The announcement comes after De Sousa was charged with three misdemeanor counts of failing to file federal income tax returns by federal prosecutors last week.

De Sousa faces up to a year in prison and a $25,000 fine for each charge, the Baltimore Sun reports.