A 68-year-old Janesville man is facing a charge of Felon in Possession of a Firearm after being caught in a sting operation. Police Sergeant Chad Pearson says Robert H. Landrum was arrested shortly before lunch Thursday. Pearson says Janesville police got a tip Landrum wanted to buy a gun and worked with the Federal Bureau of Alcohol, Tobacco, Firearms and Explsives on the case. Pearson says concerns include the fact Landrum is a convicted felon, and lifetime registered sex offender. He is also accused of making retaliatory remarks about people who'd done him wrong.