The accused “mailbox bomber” was arraigned today.It was a brief court appearance, minutes in length, following this week’s indictment of Luke Helder on two federal charges. Though he could face state and local prosecution as well, for now they’re trumped by the federal court. The charges involve crossing state lines and using explosives in crimes in which people were injured, and Jayne Kelly, Helder’s court-appointed attorney, has already announced she will not be talking with reporters leading up to or during the trial. The start date for Helder’s trial in US District Court in Cedar Rapids is September 16.