From NPR News in Washington, I'm Lakshmi Singh.Candle light vigils are being held tonight in Boston and across the nationfor the victims of the twin bombings during the Boston Marathon yesterday.At least three people were killed,one is confirmed to be 8-year-old Martin Richardwho is at the finish line of the race with his family,a second victim is identified as 29-year-old restaurant manager Krystle Campbell,according to the Associated Press which quotes Campbell's father.The identity of the third victim has yet to be confirmed.Several other people are still fighting for their lives this hour.Authorities are reporting at least 176 people were wounded, some of them critically.Doctor Geroge Velmahos, of Massachusetts general hospital, one of six sites treating patients says,some patients lost their legs but emerge from surgery saying they were just glad to be alive."We were all like extremely moved then and I think shattered by the event.Having said that our mission is to provide care,to not be stalled or hampered by our emotional reactions."He says small metallic fragments were found, some were pellets, others were like nails without heads as he puts it.Authorities are now describing the bombs found inside duffel bags as crude devices of a pressure cooker design.Now declaring the bombings an act of terrorism President Obama had a message for the perpetrators today,Americans won't be terrorized.Here is NPR's Scott Horsley.President Obama sayswhoever set off the bombs in a crowd of civilians was clearly aiming to terrorize.