The Justice Department on Friday announced a civil investigation into the Mount Vernon Police Department in suburban New York, sparked by allegations that officers used excessive force, including strip searches, and targeted Black residents.

Federal officials said they had reviewed public information, including news reports, and complaints from residents over the police department’s conduct. The agency drew scrutiny in 2019 after the disclosure of secret recordings made by officer Murashea Bovell, a whistleblower, which appeared to show that supervisors failed to investigate allegations of misconduct, as well as officers planting evidence and colluding with drug dealers.

In May, Westchester County District Attorney Mimi Rocah requested that the Justice Department intervene over what she called “pervasive and persistent” civil rights violations committed by officers.

“When officers break the law, they violate their oath and undermine the community’s trust,” Damian Williams, the U.S. attorney for the Southern District of New York, said at a news conference Friday in New York City.

The sweeping pattern-or-practice investigation is the fourth the Biden administration has launched into local law enforcement agencies this year, along with, Minneapolis, Louisville and Phoenix. The Justice Department under Attorney General Merrick Garland has reinvigorated the use of federal intervention into local policing after the Trump administration abandoned the practice, calling it federal overreach.

Such investigations typically take more than 12 months to complete and are likely to result in a court-approved consent decree mandating a lengthy series of reforms, which can take years and cost millions of dollars.

The Mount Vernon department is far smaller than the others currently under investigation, with 184 officers who patrol a majority-Black city of 70,000 just north of the Bronx. But federal officials said their investigation would be conducted in a similar manner, including interviews with police leaders, city officials and community members and a review of the department’s policies, incident reports and body-camera footage.

Assistant Attorney General Kristen Clarke said the Justice Department has received reports that officers engaged in abusive tactics against juveniles, individuals suspected of nonviolent offenses and suspects who were already in police custody.

The probe will look into allegations that officers “routinely conducted searches without a sufficient legal basis,” Clarke said, including strip searches, visual body cavity searches and manual body cavity searches.

Bovell sued the department in November 2019, after a superior allegedly called him a “rat,” which he viewed as retaliation for his efforts to expose racism and corruption, according to Gothamist and WNYC, which first reported on the secret recordings.

“We’ve struggled for years to get this message out. We’re happy the Justice Department finally heard us,” said Joseph Murray, Bovell’s attorney, who said he and his client have shared information with federal officials.

Bovell remains on the police force and was promoted to sergeant earlier this year.

Federal officials said Mount Vernon Mayor Shawyn Patterson-Howard and Police Commissioner Glenn Scott pledged to cooperate with the investigation.

A Mount Vernon police official directed questions about the federal probe to the mayor’s office. In a statement, Patterson-Howard said her office has turned over the findings of an internal police investigation that she initiated upon taking office in 2020.

“Both the Office of the Mayor and the Police Department are cooperating fully with the DOJ’s investigation and believe that the changes instituted will demonstrate that the culture of policing is changing for the better in Mount Vernon,” the mayor said.