WASHINGTON - An 18-year-old American-Muslim man who tried to set off what he thought was a car bomb outside a Chicago bar on Friday night has been arrested and charged in a federal undercover sting, US prosecutors said Saturday.They said that Adel Daoud, a US citizen who lives in the Chicago suburb of Hillside, planned for months for the attack and prayed with a man who turned out to be an undercover agent before attempting to set off a bomb in a jeep outside a bar.Gary Shapiro, acting US Attorney for the Northern District of Illinois, said in a statement the arrest followed an undercover investigation during which Daoud chose a target and worked on the alleged plot.“The explosives that Daoud allegedly attempted to detonate posed no threat to the public,” Shapiro said. “They were inert and had been supplied by undercover law enforcement personnel.”The statement claimed that law enforcement officers closely monitored Daoud’s activities and he “was offered several opportunities to change his mind and walk away from the supposed attack.”Daoud appeared in US District Court Saturday, where he has been charged with one count of attempt to use of a weapon of mass destruction (explosives) and one count of attempt to damage and destroy a building by means of an explosive. He faces a preliminary hearing today (Monday).If convicted of all charges, Daoud could be sentenced to a maximum of life in prison for attempted use of a weapon of mass destruction, and a minimum of five years and a potential maximum of 20 years in prison for attempt to damage or destroy a building by means of an explosive.An affidavit filed in support of the criminal complaint alleges Daoud used email accounts beginning in October 21011 “to obtain and distribute material, some of which he purported to author, relating to violent jihad and the killing of Americans.”Two FBI online undercover agents contacted him this spring and, during subsequent emails, he “expressed an interest in engaging in violent jihad, either in the United States or overseas,” prosecutors allege.