UPDATE 1:15 p.m. April 17:
— bailey gribben (@bailey_gribben) April 15, 2013
This eerie image (below) has surfaced online of a suspicious-looking person on a rooftop overlooking the Boston marathon, seconds before the first bomb exploded.
There has been much speculation online that he may be involved in the terrorist attack.
What do you think? Share your thoughts in the comment section below.