The FBI is asking the public for clues into the deadly Boston Marathon bombing that killed three and injured more than 170. Officials said the two shrapnel-laced devices that exploded Monday appear to have been packed into pressure cookers and then hidden inside backpacks.
msnbc's Lawrence O'Donnell will anchor the show live from Boston tonight at 10pm ET. Here's a look at the headlines we're following now.
- Investigators believe Boston bombs were pressure cookers hidden in backpacks, officials say
- Watch: Obama calls attack in Boston an ‘act of terror’
- Motive unknown: Investigation in Boston bombing continues
- Obama to visit Boston on Thursday
- Dorchester boy killed in bomb blast; mom and little sister badly hurt
- Second Boston Marathon bombing victim identified as 29-year-old woman
- Carlos Arredondo, the man in the hat at the Boston Marathon, didn’t set out to be hero
- Reporter shares account of bomb blasts at marathon