CHICAGO

- The U.S. Justice Department is expected to launch a wide-ranging investigation this week into the patterns and practices of the Chicago Police Department after recent protests following the release of a video showing a white Chicago police officer shooting a black teenager 16 times, a person familiar with the matter told the Associated Press yesterday.

The source - who spoke on the condition of anonymity - said the Justice Department is expected to make the announcement of a civil-rights investigation this week.

The civil-rights probe follows others recently in Baltimore and Ferguson, Mo., and it comes as the police department and Mayor Rahm Emanuel are under intense scrutiny over their handling of the October 2014 death of 17-year-old Laquan McDonald. Officer Jason Van Dyke was charged with first-degree murder Nov. 24, more than a year after the killing and just hours before the release of police dashboard camera footage showing the officer shooting the teenager.

The video shows McDonald veering away from officers on a four-lane street when Van Dyke, seconds after getting out of his squad car, opens fire from close range. The officer continues shooting after McDonald crumples to the ground and is barely moving. The video does not include sound, which authorities have not explained.

The Chicago City Council signed off on a $5 million settlement with McDonald's family even before the family filed a lawsuit and city officials fought in court for months to keep the video from being released publicly. The city's early efforts to suppress its release coincided with Emanuel's re-election campaign, when the mayor was seeking African-American votes in a tight race.

Since the release of the video, Emanuel forced Police Superintendent Garry McCarthy to resign and formed a task force to examine the department. But the calls for the mayor to resign - something he said he won't do - have grown louder from protesters in the city, including more than 200 people who shouted that he step down during an afternoon march yesterday. Protesters counted to 16 in reference to the shots fired, a number that has taken on a symbolic significance since the demonstrations began.

The Rev. Jesse Jackson, who was on hand for yesterday's demonstration in Chicago, said he is pleased with the decision to investigate Chicago. Jackson said he hoped that the investigation would focus not only on the police department, but on Emanuel's office and the Cook County State's Attorney's office, which he and others have criticized for taking so long to bring charges against Van Dyke.

"All three of them - the police, City Hall and the prosecutor's office - are suspect," Jackson said. "We cannot trust them."

Emanuel initially said a federal civil-rights investigation of Chicago police tactics would be "misguided" because the U.S. Attorney's office in Chicago was already investigating the incident. But Emanuel later reversed course and said he would welcome the Justice Department's involvement - something that politicians including Democratic presidential candidate Hillary Clinton and Illinois Attorney General Lisa Madigan have called for.

On Friday, Chicago released hundreds of pages that show police officers initially reported a very different version of the encounter with McDonald than the video shows. That further angered activists and protesters, who were already accusing the city of covering up what really happened the night McDonald was killed.

Neither Emanuel's office nor the police department immediately responded to a request for comment on reports of a federal investigation.

The Justice Department in the last six years has opened more than 20 investigations of police departments. In March, the department released a scathing report of the Ferguson, Mo., police force that found pervasive civil rights abuses, and in May, it reached a settlement with Cleveland police that called for sweeping improvements - including to that department's use-of-force policies. It opened an investigation of Baltimore police in May after demonstrations there turned violent in response to the death of a black man in police custody.