(CBS) – The federal probe into the Chicago Police Department is ongoing, but results could come soon, US. Attorney Zachary Fardon said Monday.

“We’re not done yet, but we’re working at a record pace,” Fardon told the City Club of Chicago.

In December, the U.S. Justice Department launched an expansive investigation into the “patterns and practices” of the CPD.

“I believe what we are going through now with CPD was inevitable and essential,” he said.

“We’ve analyzed tons of data, interviewed tons of witnesses, held public forums, conducted ride-alongs with patrol officers, reviewed CPD policies and procedures, scrutinized CPD training, conferred with top experts across the country,” the prosecutor said. “This is the largest pattern and practices investigation in the history of the Department of Justice.”

Fardon’s office is separately investigating the October 2014 police-involved shooting death of black teen Laquan McDonald, which spawned the DOJ investigation.

Also Monday, Fardon talked about the violent crime in Chicago and pointed to a screen with several photos of children who have been shot in the city.

He says Chicago is often times a tale of two cities, “one safe and bucolic, the other dangerous and volatile.”

“Our institutions have to do better, law enforcement has to do better, government has to do better schools, non for profits — we all have to do better,” Fardon said.