An FBI poster showing the devil tattoo on escaped bank robber Kenneth Conley's upper right arm. (Credit: Bandit Tracker Chicago)

An FBI poster showing the devil tattoo on escaped bank robber Kenneth Conley’s upper right arm. (Credit: Bandit Tracker Chicago)

CHICAGO (CBS) — The FBI has expanded its search for a convicted bank robber who is still on the lam nearly two weeks after escaping the federal jail in downtown Chicago.

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WBBM Newsradio’s Brandis Friedman reports Kenneth Conley and his cellmate – Joseph “Jose” Banks – escaped from the Metropolitan Correctional Center on Dec. 18. Banks was captured a few days later, but Conley has yet to be caught.

FBI Special Agent Joan Hyde said, because of the time that’s passed since Conley’s escape and because he’s been known to travel, the search has broadened to nationwide.

“Unfortunately, we’ve had no recent reports of sightings. We continue to search; we’ve broadened the search, it is certainly a nationwide search at this point,” Hyde said. “The time that has passed has allowed him, perhaps, to travel outside the area. He’s also been known to travel in the past.”

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The FBI is hoping a new photo will help the public spot Conley and turn him in.

“We have obtained a photograph of a rather unique tattoo that Mr. Conley has on his upper right arm. It is a picture of a devil,” Hyde said. “While he may change his appearance with his hair, his facial hair, that sort of thing, it would be very hard to remove or disguise that tattoo.”

Conley’s photo has been posted on flyers at all FBI offices across the country and on the FBI’s “Bandit Tracker” website.

Conley and Banks — both convicted bank robbers — escaped from the MCC on Dec. 18, by making a rope out of bedsheets, removing bars from the window of their cell, and chipping away at the concrete around the window to make the narrow opening large enough to slip out and scale down 15 stories.

Shortly after Conley and Banks escaped, a security camera at a private building in the South Loop recorded them getting into a cab near Congress Parkway and Michigan Avenue. The two briefly visited the home of one of Conley’s relatives in Tinley Park.

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Banks was arrested early three days after the escape at an apartment building in the 2300 block of North Bosworth Avenue, but Conley hasn’t been seen since their escape.