Prosecutors say Finton tried to set off a car bomb outside the federal courthouse in Springfield, but FBI agents posing as Al Qaida operatives gave Finton a decoy device before taking him into custody.
Finton attended a mosque in Decatur.
Friday, the leaders of that mosque thanked federal and local authorities for acting quickly in arresting Finton.
"We, the Muslims of Decatur Illinois, condemn acts of terrorism, or attempted acts of terrorism, and we equally condemn those who committ terror," Imam Johnnie Shabazz Masjid Wali Hassen said.
Finton remains in custody pending action by a grand jury.
