CNBC's John Harwood reports the White House is now handling the Boston explosions as an "act of terror;" and former assistant secretary for homeland security Robert Liscouski, weighs in.
Stratfor's vp for intelligence Fred Burton offers insight on the 2 explosions near the finish line of the Boston Marathon.
A Boston Marathon spectator describes what he heard as 2 explosives went off near the finish line, and the security that took action thereafter.
Former Secretary of Homeland Security Tom Ridge says the explosives at the Boston Marathon is "a pretty basic device," and discusses the importance of gathering information to finding the perpetrator.
CNBC's John Harwood recaps what President Obama said on the investigations on the 2 explosions in Boston today.
President Obama addresses the 2 explosions near the finish line of the Boston Marathon. "We still do not know who did this, and we will hold them accountable," he says.
A runner from the Boston Marathon explains the 2 explosions she heard near the finish line.
CNBC's Bertha Coombs and NBC's Pete Williams offer the latest reports on the 2 explosions that occurred near the finish line of the Boston Marathon.
Boston Mayor Thomas Menino and Massachusetts Gov. Deval Patrick discuss the investigation into the 2 explosions near the finish line of the Boston Marathon.
KNBC-TV's Alycia Lane had a friend running in the Boston Marathon and describes the panic when 2 explosives went off at the finish line.
Eyewitness Dan McCurio explains that he had just finished the race when the explosions went off. "It was kind of unbelievable," he says. "The ground was shaking."
NBC's Pete Williams reports authorities are still looking at packages found on the streets, and destroying any packages they cannot resolve immediately.
Universal Sports' Dean Walker heard the first explosion and saw the second at the Boston Marathon, and discusses how long the lock down might occur.
White House correspondent Chuck Todd reports President Obama has now gotten 2 briefings on the Boston Marathon explosions.
Eyewitness Mike Capos shares what he saw and heard after 2 explosives went off at the finish line of the Boston Marathon.
Boston Globe's David Abel was among the witnesses at the finish line at the Boston Marathon.
NBC's Pete Williams discusses the precautions being taken in Boston after 2 separate incidents in occurred, one at the Boston Marathon and one at the JFK Library.
Former Boston Police Commissioner William Bratton says after 2 hours since the 2 explosives went off at the finish line of the Boston Marathon, the area has cleared.
A photographer at the finish line of the Boston Marathon, Steve Silva, explains the scene he saw as 2 explosions went off near the finish line of the Boston Marathon, with NBC's Brian Williams.
In a news conference, the Boston police reveal what they know happened today along the route of the Boston Marathon.