Civil rights officials from the U.S. Department of Justice announced Tuesday that the Trenton Police Department is under investigation.

The federal prosecutors detailed allegations of police illegally stopping and searching people, with minorities bearing the brunt of police action. Concerns about use-of-force patterns by Trenton police will also be a focus of the probe.

The launch of the investigation was applauded by civil rights advocates as the first step in a process they hope will lead to lasting reform.

Trenton Mayor Reed Gusciora, however, defended the city’s police and said the probe will ultimately distract from law enforcement efforts to combat crime in Trenton.

The investigation will likely take months, or even longer, to play out. Depending on the findings, the Trenton Police Department could by subject to federal oversight through a consent decree, in a similar process that has guided reform of the Newark Police Department in recent years.