Nation mourns Boston bombing victims
Three people were killed when two homemade explosives went off at the Boston Marathon on April 15, 2013, and a campus police officer at the Massachusetts Institute of Technology was fatally shot in the manhunt that followed. From left, the victims were Krystle Campbell, Sean Collier, Lingzi Lu and Martin Richard. Click through the gallery to see how the victims were honored and remembered in the weeks after the terror attack.
Nation mourns Boston bombing victims
People pause at the memorial site in Boston's Copley Square on April 30, 2013.
Nation mourns Boston bombing victims
Running shoes were among the mementos left as a tribute to the bombing victims.
Nation mourns Boston bombing victims
Boston showed its resilience and heart with signs of support for the bombing victims, including this cover from an issue of Boston magazine.
Nation mourns Boston bombing victims
Law enforcement officials enter St. Patrick's Church prior to Collier's funeral in Stoneham, Massachusetts, on April 23, 2013.
Nation mourns Boston bombing victims
President Barack Obama observes a moment of silence in the White House Oval Office on April 22, 2013.
Nation mourns Boston bombing victims
Staff members of the Beth Israel Deaconess Medical Center gather inside a trauma room to observe a moment of silence on April 22, 2013.
Nation mourns Boston bombing victims
A Buddhist sits at a memorial near the marathon finish line during a moment of silence on April 22, 2013.
Nation mourns Boston bombing victims
One week after the bombings, people gather to observe a moment of silence in Copley Square.
Nation mourns Boston bombing victims
Officials line Boylston Street as they observe a moment of silence near the marathon finish line on April 22, 2013.
Nation mourns Boston bombing victims
People take part in the moment of silence near the marathon finish line.
Nation mourns Boston bombing victims
State employees pause for a moment of silence on the steps of the Massachusetts State House.
Nation mourns Boston bombing victims
Pallbearers carry Campbell's casket after a funeral service in Medford, Massachusetts, on April 22, 2013.
Nation mourns Boston bombing victims
Mourners walk out of St. Joseph Catholic Church after Campbell's funeral service.
Nation mourns Boston bombing victims
Nurse practitioner Maureen Quaranto, who treated victims of the bombings, wears her Boston Marathon jacket during Mass on April 21, 2013.
Nation mourns Boston bombing victims
From left, Boston Police Department Superintendents Kevin Buckley and William Evans attend Mass with Police Commissioner Edward Davis on April 21, 2013.
Nation mourns Boston bombing victims
Photos of the deceased are displayed in Boston at the Cathedral of the Holy Cross on April 21, 2013.
Nation mourns Boston bombing victims
Leaders of an interfaith service participate in a vigil near the finish line on April 21, 2013.
Nation mourns Boston bombing victims
A makeshift memorial honors the bombing victims on April 21, 2013.
Nation mourns Boston bombing victims
Nicole Collier Lynch, Collier's sister, hugs a police officer during a vigil in Wilmington, Massachusetts, on April 20, 2013.
Nation mourns Boston bombing victims
People gather at a makeshift memorial in Boston on April 20, 2013.
Nation mourns Boston bombing victims
Huntsville, Alabama, residents hold a prayer vigil on April 19, 2013.
Nation mourns Boston bombing victims
A man rings a bell at the vigil in Huntsville.
Nation mourns Boston bombing victims
Two women embrace during a candlelight vigil in Somerville, Massachusetts, on April 18, 2013.
Nation mourns Boston bombing victims
Obama talks with staff members at Massachusetts General Hospital while visiting injured patients on April 18, 2013.
Nation mourns Boston bombing victims
A man at a Boston restaurant watches Obama speak on television on April 18, 2013.
Nation mourns Boston bombing victims
Mourners fill a Boston cathedral for an interfaith service on April 18, 2013.
Nation mourns Boston bombing victims
Obama, first lady Michelle Obama and Massachusetts Gov. Deval Patrick attend the interfaith prayer service.
Nation mourns Boston bombing victims
Flowers, running shoes and other items are left in memory of bombing victim Lingzi Lu.
Nation mourns Boston bombing victims
Dennis Seidenberg of the Boston Bruins observes a moment of silence before the start of an NHL hockey game in Boston on April 17, 2013. It was the first sporting event held in the city after the bombings.
Nation mourns Boston bombing victims
Danielle Cerroni writes a chalk message on the street near the marathon's finish line on April 17, 2013.
Nation mourns Boston bombing victims
A woman looks at memorials left at the scene of the attack.
Nation mourns Boston bombing victims
A crowd gathers at Boston's Garvey Park during a vigil for bombing victim Martin Richard on April 16, 2013.
Nation mourns Boston bombing victims
A woman uses her hand to keep wind from her candle during an interfaith service in Boston on April 16, 2013.
Nation mourns Boston bombing victims
Mourners gather on the edge of the pond for a candlelight vigil in Boston on April 16, 2013.
Nation mourns Boston bombing victims
Students from the Clifden Academy hold an American flag and candles during a vigil in Dorcester, Massachusetts, on April 16, 2013.
Nation mourns Boston bombing victims
People walk along the barricade at Boylston Street on April 16, 2013.
Nation mourns Boston bombing victims
Mourners in Boston hug one another during a vigil for victims on April 16, 2013.
Nation mourns Boston bombing victims
Five-time Boston Marathon runner Jose Sotolongo, center, reacts during a moment of silence in Miami on April 16, 2013.
Nation mourns Boston bombing victims
The New York Islanders and Florida Panthers stand for a moment of silence before an NHL hocky game in Uniondale, New York, on April 16, 2013.
Nation mourns Boston bombing victims
Members of the Boston Red Sox observe a moment of silence before their Major League Baseball game in Cleveland on April 16, 2013.
Nation mourns Boston bombing victims
From left, Boston Marathon runners Tammy Snyder, Diane Deigmann and Lisa Kresky-Griffin embrace at the barricaded entrance to Boylston Street on April 16, 2013.
Nation mourns Boston bombing victims
Two young girls leave flowers on the steps outside the Boston home of 8-year-old bombing victim Martin Richard on April 16, 2013.
Nation mourns Boston bombing victims
Traders at the New York Stock Exchange observe a moment of silence before the opening bell on April 16, 2013.
Nation mourns Boston bombing victims
The flag above the White House flies at half-staff on April 16, 2013.
Nation mourns Boston bombing victims
The Minnesota Twins stand during the national anthem before a baseball game in Minneapolis on April 15, 2013.
Nation mourns Boston bombing victims
Obama makes a statement about the bombings on April 15, 2013.
Nation mourns Boston bombing victims
Players and fans observe a moment of silence before an NBA game in Oakland, California, on Aprl 15, 2013.
Nation mourns Boston bombing victims
An American flag flies at half-staff at the Capitol building in Washington on April 15, 2013.
Nation mourns Boston bombing victims
Hockey fans in Glendale, Arizona, pause for a moment of silence before a game on April 15, 2013.