CHICAGO (CBS) — Federal prosecutors who sent former police Cmdr. Jon Burge to prison for lying about the torture of criminal suspects have now turned their attention to detectives implicated in torture, and to former Cook County prosecutors.

As WBBM Newsradio 780′s Mike Krauser reports, when Burge was convicted of perjury last year, U.S. Attorney Patrick Fitzgerald promised the investigation into police torture allegations — dating to the 1970s and ’80s — was not over.

LISTEN: Newsradio 780′s Mike Krauser reports

Now, the Chicago Tribune is reporting, investigators are looking at old court cases involving detectives under Burge – who could not be tried for torture because the statute of limitations.

Several detectives have been accused of obtaining confessions through torture, and there are allegations that Cook County prosecutors played a role in railroading the innocent.

In some cases, charges were later dismissed or the suspects were acquitted, and filed wrongful conviction lawsuits.

Specifically, the feds are probing the 1990 murder and rape accusation that resulted in life prison sentences against Harold Hill and Dan Young Jr., who were exonerated by DNA and released in 2005, the Tribune reported.

Burge was convicted last year of lying about torturing prisoners into making confessions. He was sentenced in January to 4 1/2 years in prison, and reported to a federal penitentiary in Raleigh, N.C., in March.

Since Burge was fired from the Police Department in 1993, his name has become synonymous with police brutality in Chicago.

Dozens of suspects accused Burge and the detectives under their command of shocking them with a homemade electrical device, suffocating them with typewriter bags, putting guns to their head and playing Russian roulette — all to force them to confess to murders they didn’t commit.