The former cellmates apparently broke a cell window, pulled out the bars then descended almost 20 stories to escape the downtown Metropolitan Correctional Center early Tuesday.
Joseph "Jose" Banks, 37, and Kenneth Conley, 38, were unaccounted for during a 5 a.m. headcount, according to the U.S. Marshals Service. An FBI affidavit says the men were in their assigned areas for a head count around 10 p.m. Monday and that jail employees noticed the makeshift rope around 7 a.m. Nearby business owners said helicopters and canine units did not swarm the area until almost 8:30 a.m.
Inside the cell Tuesday morning, investigators found a broken window and bars inside a mattress, according to an FBI affidavit. Stuffed under blankets on two beds were clothing and sheets, shaped to resemble a body, the affidavit said.
Hours after the escape, the rope of bed sheets could be seen dangling down the side of the building, at least 200 feet long and knotted about every 6 feet.
The FBI has declined to provide details of the escape, but a close-up photograph clearly shows damage to the concrete along the lower edge of the window, which is 6 feet tall but only 6 inches wide. Damage broadened the hole through which the men must have had to climb.
Banks and Conley were the first inmates to escape from the federal facility in nearly two decades. It was still unclear how they were able to accumulate enough bed sheets and other items to pull off the escape or how jail guards failed to detect the scheme or notice that the men were gone until several hours later.
The FBI reissued a plea to the public to be on the lookout for the men, whom they believe are traveling together, and warned that they should be considered armed and dangerous. On Wednesday, Thomas Trautmann, the acting special agent-in-charge of the FBI's Chicago office, announced a $50,000 reward leading to their arrests.
The apparently meticulously planned escape from the 27-story facility came just a week after Banks made a courtroom vow of retribution. The men, who have yet to be sentenced, are facing hefty prison terms.
The facility, which can house up to 700 inmates, is one of the only skyscraper lockups in the world, and experts 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, U.S. Marshal's Service spokeswoman Belkis Cantor said.
Banks and Conley both were wearing orange jumpsuits, but police believe they quickly changed into white T-shirts, gray sweatpants and white gym shoes. The FBI believes both men were in Tinley Park, a heavily wooded area about 25 miles south of Chicago. Authorities were scouring a local forest preserve in the afternoon.
SWAT teams stormed at least one home in Tinley Park on Tuesday. Although neither man was found, evidence suggested that both had been at the home just hours earlier, according to the FBI. On Wednesday, police in neighboring Orland Park said a search had been conducted Tuesday of a home where an associate of Conley lived or once lived, but that search came up empty as well.
Some schools went on lockdown after being inundated with calls from nervous parents. Mike Byrne, a superintendent in Tinley Park, said "our parents are so emotionally charged right now" because of the school shootings in Connecticut.
Banks, known as the Second-Hand Bandit because he wore used clothes during his heists, was convicted last week of robbing two banks and attempting to rob two others. Authorities say he stole almost $600,000, and most of that still is missing.
During trial, he had to be restrained because he threatened to walk out of the courtroom. He acted as his own attorney and verbally sparred with the prosecutor, at times arguing that U.S. law didn't apply to him because he was a sovereign citizen of a group that was above state and federal law.
After he was convicted by U.S. District Judge Rebecca Pallmeyer, he said he would "be seeking retribution as well as damages," the Chicago Sun-Times and Chicago Tribune reported.
When the judge asked how long he needed to submit a filing, Banks replied: "No motion will be filed, but you'll hear from me."
Pallmeyer, a prominent federal judge who oversaw the corruption trial of now imprisoned former Illinois Gov. George Ryan, appeared to stick to her regular schedule Tuesday and there were no signs of extra security. Her office declined comment.
Conley pleaded guilty last October to robbing a Homewood Bank last year of nearly $4,000. Conley, who worked at the time at a suburban strip club, wore a coat and tie when he robbed the bank and had a gun stuffed in his waistband.
The brother of Hollywood director Christopher Nolan also tried to escape in 2010. Matthew Nolan, who was being held pending an extradition request, was sentenced to 14 months in jail for plotting to escape the high-rise jail by hiding a rope made out of bed sheets in his cell.
Associated Press writer Sara Burnett contributed to this report.