They have 2 possible suspects...well, three, but two of them appear to be working as a team.
Two are an elderly retired couple who are believed to be radical Tea Party supports. The man was carrying what has been described as a deadly looking cane.
The other suspect was a 30-35 year old white Caucasian male, seen cheering suspiciously for one of the runners at the finish line. He was wearing clothing associated with militant gangs, an NRA ball cap and a Gadsden Flag T-Shirt.
Do not approach or attempt to detain these suspects if seen, they are considered armed and dangerous.