Tracked by police from Dayton, Ohio, he was captured and jailed in Lima. After searching him before letting him into the prison, the police discovered a document which appeared to be a prison escape plan. They demanded Dillinger tell them what the document meant, but he refused.[5]
Dillinger had helped conceive a plan for the escape of Pierpont, Clark and six others he had met while previously in prison, most of whom worked in the prison laundry. Dillinger had friends smuggle rifles into their prison cells which they used to escape, killing two guards, four days after Dillinger's capture. The group known as the "first Dillinger gang" included Pierpont, Clark, Charles Makley, Edward W. Shouse, Jr. of Terre Haute, Harry Copeland, James "Oklahoma Jack" Clark, Walter Dietrich and John "Red" Hamilton. Three of the escapees arrived in Lima on October 12, where they impersonated Indiana State Police officers, claiming they had come to extradite Dillinger to Indiana. When the sheriff asked for their credentials, they shot him and beat him unconscious, then released Dillinger from his cell. The four men escaped back into Indiana where they joined the rest of the gang.[5]