Obama: FBI Investigating As 'Act Of Terrorism'... Still No Suspects... Governor: No Unexploded Devices Were Found... 3 Dead, 176 Injured... 8-Year-Old Killed, Mother And Sister Seriously Injured... Father Speaks... Brothers Each Lose A Leg In Blasts... 'At Least 25 To 30 People Have At Least 1 Leg Missing'... Doctor: 'This Amount Of Carnage... Is What We Expect From War'... NYT Source: Saudi Person Of Interest Not Involved In Attack... Cities Worldwide On Alert... Report: Explosives Made Of Pressure Cookers With Metal, Ball Bearings... How To Help... LIVE UPDATES

Medical workers aid injured people at the finish line of the 2013 Boston Marathon in Boston, Monday, April 15, 2013. Two bombs exploded near the finish line of the Boston Marathon on Monday, killing at least two people and injuring dozens of others (AP Photo/Charles Krupa)

The only two bombs at the Boston Marathon were those detonated at the finish line, Massachusetts Gov. Deval Patrick said Tuesday at a press conference.

Several bags and backpacks had been deemed suspicious in the initial hours after the attack, but no additional bombs were found, the governor said.

Special Agent Gene Marquez of the Bureau of Alcohol, Tobacco, Firearms and Explosives said that authorities are following a "variety of leads," though no suspects have been named. READ More...