WASHINGTON - The Justice Department plans to launch an investigation into the patterns and practices of the Chicago Police Department, a wide-ranging review similar to those that scrutinized the police departments in Ferguson, Mo., and Baltimore, according to several law enforcement officials.

The civil probe, which the officials say could be announced this week, comes as Chicago continues to grapple with protests after the release of a video showing the police shooting of Laquan McDonald, which prompted murder charges for the officer involved and the resignation of the city's police chief. The Justice Department is already investigating the McDonald shooting, but this new investigation by the department's civil rights division would focus on the police department's practices broadly to determine whether any of them contribute to civil rights violations.

A spokesman for the Chicago Police Department said Sunday morning that he did not know anything about the possibility of a second, broader federal probe into the force. A Justice Department representative did not confirm that a new probe into the Chicago police is imminent.

"Civil rights division lawyers are reviewing the many requests for an investigation, which is the department's standard process, and the attorney general is briefed regularly on the review and expects to make a decision very soon," a department official said.

Mayor Rahm Emanuel, a former top aide to President Obama, called the possibility of a civil rights investigation "misguided" last week. But, a day later, he reversed course and said he would welcome such an investigation.

Emanuel has come under fire for his administration's handling of the McDonald video, specifically for fighting its release for more than a year, which some have suggested was a politically motivated decision meant to insulate the mayor from political backlash while he was locked in a tight reelection effort. One week after the McDonald video was released, Emanuel fired Police Superintendent Garry F. McCarthy.

"I welcome the engagement of the Justice Department," Emanuel told reporters during a ribbon-cutting ceremony Thursday. "We have a long road ahead of us as a city, and I welcome people from many views to help us do what exactly we need to do."

On the same day that McCarthy was fired, Illinois Attorney General Lisa Madigan wrote a letter to the Justice Department urging them to open an investigation into the police department. "The McDonald shooting is shocking, and it highlights serious questions about the historic, systemic use of unlawful and excessive force by Chicago police officers and the lack of accountability for such abuse by CPD," Madigan wrote.

"We have called for police reform as it relates to this police department . . . and we've also called for accountability in city government," said Rose Joshua, president of Chicago South Side NAACP, which had previously called for a Justice Department probe into the city's police. "It should be something that's broad. It should be a detailed probe and should look into the specific civil rights complaints filed over the years by activists here on the ground."

Joshua said that she welcomes the federal probe and hopes that it will address the underlying policing issues.