WASHINGTON (WJZ/AP) — The Justice Department is preparing to announce a civil rights investigation into the Baltimore Police Department.

CBS News reporter Paula Reid confirms Attorney General Loretta Lynch will launch a pattern or practices investigation as soon as Friday.

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Baltimore Mayor Stephanie Rawlings-Blake on Wednesday asked the Justice Department to investigate the policing practices of the entire city police force. The request followed the unrest that roiled the city after the death of a 25-year-old man who was severely injured in police custody.

Baltimore had already been participating in a voluntary Justice Department review.

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Attorney General Loretta Lynch told a Senate subcommittee on Thursday that more may need to be done.

In her first appearance before Congress since being sworn in last week, Lynch said she was in the process of considering the request for a full-fledged civil rights investigation.

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