Capitol Hill police say there is no known connection between the bombings against the Boston Marathon and Washington but they are warning Congress and their staffers to be vigilant.
A warning notice sent out to staff, obtained by The Associated Press on Monday, says the Capitol Police are stepping up their numbers in anticipation of more security checks and more suspicious packages reported over the coming days. They also warned of tighter security at entryways, including more frequent canine inspections of visitors.
The notice says the "increased presence and visibility is a proactive response" to the events in Boston, rather than being based on any specific threat.
Many congressmen called the bombings terrorism, but said it was too soon to know if the attack or attackers were domestic or foreign.