Scenes from Boston bombing manhunt
A look at the past 24 hours.
STFInvestigators carry boxes into a building on Norfolk Street as the search for one of the Boston Marathon bombing suspects continues in Cambridge, Mass., Friday, April 19, 2013. Two suspects in the Boston Marathon bombing killed an MIT police officer, injured a transit officer in a firefight and threw explosive devices at police during their getaway attempt in a long night of violence that left one of them dead and another still at large Friday, authorities said as the manhunt intensified for a young man described as a dangerous terrorist.(AP Photo/Michael Dwyer)