CBS: PHILADELPHIA (CBS 3) — A threatening letter containing a suspicious powder forced evacuations at a Barack Obama campaign office in South Philadelphia Tuesday afternoon. According to police, a letter with a suspicious powder was sent to an Obama-Biden field office in the 1500 block of Christian Street. The letter was apparently opened by a volunteer at the office.”The letter was somewhat threatening in nature and it contained a substance that we believe to be a hazmat,” Captain Mike Gillespie said shortly after the incident. Police, fire and hazmat crews responded to the scene shortly after a 911 call was […]