BENTON, Ill. (AP) — The federal trial for a Chicago man accused of mailing violent threats to Southern Illinois University’s Carbondale campus has been again postponed as he awaits a mental competency hearing. Derrick Dawon Burns’ trial in Benton was first set for early February and then rescheduled to begin Monday. The new trial date is June 15, preceded by a court-ordered psychiatric review on April 23. Burns has pleaded not guilty to felony charges related to threatening mailings he allegedly sent in 2012 and 2013. Investigators say most of the letters suggested the campus would be targeted with violence ranging from rapes to beheadings. The letters also threatened arson, the use of pipe bombs, shooting rampage and the unleashing of “deadly chemical powder.” One mailing prompted the precautionary evacuation of campus dormitories.