CHICAGO (AP) - Two convicted bank robbers are at large after using a knotted rope or bed sheets to escape from a federal prison window high above downtown Chicago early Tuesday, a week after one of them made a courtroom vow of retribution.
    
The escape occurred sometime between 5 a.m. and 8:45 a.m. when the inmates were discovered missing, Chicago Police Sgt. Mark Lazarro said. Hours later, what appeared to be a rope, knotted at six-foot intervals, could be seen dangling into an alley on the side of the Metropolitan Correctional Center from a window approximately 20 stories from the ground.
    
Lazarro said 37-year-old Jose Banks and 38-year-old Kenneth Conley had been wearing prison-issue orange jumpsuits, but that they could now be wearing white t-shirts, gray sweat pants and white gym shoes.
    
The FBI said in a statement that the men were last seen together in the Tinley Park area, about 25 miles southwest of Chicago and that they should be considered armed and dangerous.
    
Banks is described as a black man, 5-feet-8, weighing 160 pounds. Conley is described as white, 6-feet-tall, weighing 185 pounds.
    
Banks was convicted by a federal jury last week after a trial during which he was restrained to a chair because he was threatening to walk out of the courtroom. He told the judge: "You'll hear from me."
    
Ten deputy U.S. marshals were in the courtroom when the verdict was announced.

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