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Two inmates escape from high-rise jail in Chicago

Scott Olson/Getty Images

Crime scene tape surrounds the federal Metropolitan Correctional Center in the Loop after two convicted bank robbers escaped on December 18, 2012 in Chicago, Illinois.

CHICAGO — A massive manhunt is underway for two bank robbers who pulled off a daring escape from downtown Chicago’s high-rise jail Tuesday by apparently squeezing through a narrow window and scaling down about 20 stories using a makeshift rope.

The two men were first unaccounted for during a 5 a.m. head count, but it is unclear if they were still inside the 27-story Metropolitan Correctional Center at the time, US Marshal’s Service spokeswoman Belkis Cantor said.

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Local shop owners say police did not swarm the area until more than three hours later, when what appeared to be a rope, knotted at 6-foot intervals, could be seen dangling from a window about 20 stories up.

Investigators later found a broken window in the men’s cell, where window bars were found inside a mattress, according to an FBI affidavit filed late Tuesday. Fake metal bars also were found in the men’s cell, a rope was tied to a window bar, and each man’s bed was stuffed with clothing and sheets to resemble a body, the affidavit said.

It appeared to illustrate a meticulously planned escape — which came a week after Joseph Banks, 37, made a courtroom vow of retribution. He and Kenneth Conley, 38, are facing hefty prison sentences, and the FBI said they should be considered armed and dangerous.

The men had been wearing prison-issue orange jumpsuits, but now might be wearing white T-shirts, gray sweat pants, and white gym shoes, Chicago police Sergeant Mark Lazarro said.

The FBI said that the men were last seen together in the Tinley Park area, about 25 miles southwest of Chicago.

SWAT teams stormed a Tinley Park home early Tuesday afternoon, but the fugitives were not there, FBI Special Agent Frank Bochte said.

Banks is described as 5 feet 8 inches, weighing 160 pounds. Conley is described as 6 feet tall, weighing 185 pounds.

The men apparently descended from a thin window barely half a foot wide on the flat south side of the jail into the alley below.

The facility is one of the only skyscraper lockups in the world, and specialists say its triangular shape was meant to make it easier to guard, theoretically reducing blind spots for guards. The only other escape from the nearly 40-year-old facility occurred in the mid-1980s.

Banks was convicted last week of robbing two banks and attempting to rob two others. Authorities say he stole almost $600,000.

After he was convicted, he said he would ‘‘be seeking retribution as well as damages,’’ the Chicago Sun-Times and Chicago Tribune reported.

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