Chicago Mayor Rahm Emanuel listens to remarks at a news conference in Chicago, Dec. 7, 2015. Reuters

As pressure mounts in Chicago for Mayor Rahm Emanuel to resign, the city is promising to release all emails pertaining to Laquan McDonald, the teenager shot 16 times and killed by Chicago police in October 2014. Video of the shooting – released 13 months after his death -- is graphic and shows a single officer, Jason Van Dyke, firing on the young man and continuing to fire for 14 to 15 seconds after McDonald had fallen to the ground.

Thousands took to the streets to protest police brutality and call for Emanuel’s resignation after the video was released, and Van Dyke was formally indicted Tuesday by a grand jury on six counts of first-degree murder and one count of official misconduct. An email response to a Freedom of Information Act request for all documents related to the shooting was issued Wednesday saying that all nonexempt files would be provided by Dec. 31.

A protester yells during a demonstration outside the office of Chicago Mayor Rahm Emanuel in Chicago, Dec. 7, 2015. Reuters

The crisis has attracted the attention of the United States Justice Department, an arm of the federal government under the purview of Emanuel’s former boss President Barack Obama. Emanuel was Obama’s chief of staff from the president’s inauguration until 2010, when he started his mayoral bid in Chicago. Emanuel was scheduled to meet with Department of Justice officials Thursday.

“We welcome them. They're here. We're going to fully cooperate, everybody. It is in our self-interest as a city that they're here,” Emanuel said of the probe. The investigation is expected to take more than a year to be completed.

Protesters are planning to put economic pressure on the mayor and city to force Emanuel’s resignation. The activists have demanded that other elected officials ask the mayor to step down and are planning a march on Chicago’s famous Michigan Avenue – part of which is a shopping strip also known as the “Magnificent Mile” – on Christmas Eve in order to disrupt last-minute shopping there.