Investigators scour the area for any clues ← Related Article Visit The Boston Globe Share on Twitter Share on Facebook Comment on this Scroll to top of page Aram Boghosian for The Boston Globe Sam Galvin of West Roxbury added candles to a makeshift memorial on the barricades blocking off Boylston Street. Julio Cortez/AP Lizzie Lee, 56, of Lynwood, Wash., who had participated in her first Boston Marathon, holds a candle and a flower at a vigil at Boston Common. Aram Boghosian for The Boston Globe Members of the military walked along Boylston Street near the finish line of the Boston Marathon. Yoon S. Byun/globe staff Emily Gillis, 7, her brother Conor, 4, of Dorchester, and their cousin Benjamin McCormick, 8, of Milton attended a vigil for blast victim Martin Richard at Garvey Park in Dorchester. SHANNON STAPLETON/REUTERS Vigil-goes held candles to honor the victims. John Tlumacki/Globe Staff Investigators were combing through the aftermath of the deadly Boston Marathon terrorist attack Tuesday. John Tlumacki/Globe Staff Two people stood above 755 Boylston St. John Tlumacki/Globe Staff A wide view of the scene Tuesday. John Tlumacki/Globe Staff The scene outside of Marathon Sports, the site of the first bomb explosion. John Tlumacki/Globe Staff Police tape blocked off access to the area. MATTHEW CAVANAUGH/EPA A woman looked down Boylston Street Tuesday, toward the finish line of the Boston Marathon and the site of deadly bombings a day earlier. MATTHEW CAVANAUGH/EPA A Boston Police officer stood on Boylston Street on Tuesday. Bill Greene/Globe Staff Boston Police Department Commissioner Edward Davis spoke along with other local and federal officials Tuesday morning. Elise Amendola/Associated Press Senator Elizabeth Warren, Boston Mayor Thomas M. Menino, Governor Deval Patrick, and FBI special agent in charge Richard DesLauriers spoke at the press conference. Dina Rudick/Globe Staff Roads around Boylston Street in Boston's Back Bay were closed and considered an active crime scene on Tuesday morning. Darren McCollester/Getty Images A military police officer checked the identification of a man on Massachusetts Avenue on Tuesday morning. Evan Allen/Globe staff Neighbors have begun leaving flowers outside the Dorchester home of the eight-year-old killed during yesterday’s attack. Matthew J. Lee/Globe Staff Overnight, a wave of law enforcement officials swarmed a home of a "person of interest" on Ocean Avenue in Revere. Darren McCollester/Getty Images Special police units assembled in the Boston Common on Tuesday morning. JOHN TLUMACKI/GLOBE STAFF A woman received help following the first of two explosions on Boylston Street Monday. DAVID L. RYAN/GLOBE STAFF Just seconds after the first explosion rocked the area near the finish line, there was a second blast a few blocks away on Boylston Street. John Tlumacki/Globe Staff Police officers with their guns drawn reacted to the blast. JOHN BLANDING/ GLOBE STAFF Race volunteer Katherine Swierk (left) was reunited with her aunt Terry Days (center) and friend Jocelyn Cacio. JOHN TLUMACKI/GLOBE STAFF A victim of the first explosion near the finish line was helped on the sidewalk. JOHN TLUMACKI/GLOBE STAFF A woman knelt and prayed at the scene of the first explosion at the marathon finish line. JOHN TLUMACKI/GLOBE STAFF Boston Police examined blown-out windows at the scene of the first explosion. JOHN TLUMACKI/GLOBE STAFF A man comforted a victim near the race finish line. Across the city, people met up to seek solace amid tragedy. Bill Greene/Globe Staff Former New England Patriots lineman Joe Andruzzi carried a woman on Exeter Street after the explosions. BARRY CHIN/GLOBE STAFF School buses lined both sides of Boylston Street where the street was locked down following the explosions. ESSDRAS M. SUAREZ/GLOBE STAFF Security forces blanketed Back Bay after twin blasts rocked the area around the marathon finish line. ESSDRAS M SUAREZ/GLOBE STAFF Boston Police set up a roadblock at Gloucester and Newbury streets as officials closed down a large part of Back Bay to facilitate an investigation.