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.
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.
boston police/family photos/us attorney's office
People pause at the memorial site in Boston's Copley Square on April 30, 2013.
People pause at the memorial site in Boston's Copley Square on April 30, 2013.
arren McCollester/Getty Images
Running shoes were among the mementos left as a tribute to the bombing victims.
Running shoes were among the mementos left as a tribute to the bombing victims.
arren McCollester/Getty Images
Boston showed its resilience and heart with signs of support for the bombing victims, including this cover from an issue of Boston magazine.
Boston showed its resilience and heart with signs of support for the bombing victims, including this cover from an issue of Boston magazine.
from boston magazine
Law enforcement officials enter St. Patrick's Church prior to Collier's funeral in Stoneham, Massachusetts, on April 23, 2013.
Law enforcement officials enter St. Patrick's Church prior to Collier's funeral in Stoneham, Massachusetts, on April 23, 2013.
CJ GUNTHER/EPA/LANDOV
President Barack Obama observes a moment of silence in the White House Oval Office on April 22, 2013.
President Barack Obama observes a moment of silence in the White House Oval Office on April 22, 2013.
Pete Souza/The White House
Staff members of the Beth Israel Deaconess Medical Center gather inside a trauma room to observe a moment of silence on April 22, 2013.
Staff members of the Beth Israel Deaconess Medical Center gather inside a trauma room to observe a moment of silence on April 22, 2013.
Barry Chin/The Boston Globe/Getty Images
A Buddhist sits at a memorial near the marathon finish line during a moment of silence on April 22, 2013.
A Buddhist sits at a memorial near the marathon finish line during a moment of silence on April 22, 2013.
Kevork Djansezian/Getty Images
One week after the bombings, people gather to observe a moment of silence in Copley Square.
One week after the bombings, people gather to observe a moment of silence in Copley Square.
Mario Tama/Getty Images
Officials line Boylston Street as they observe a moment of silence near the marathon finish line on April 22, 2013.
Officials line Boylston Street as they observe a moment of silence near the marathon finish line on April 22, 2013.
JESSICA RINALDI/REUTERS/LANDOV
People take part in the moment of silence near the marathon finish line.
People take part in the moment of silence near the marathon finish line.
Kevork Djansezian/Getty Images
State employees pause for a moment of silence on the steps of the Massachusetts State House.
State employees pause for a moment of silence on the steps of the Massachusetts State House.
JUSTIN LANE/EPA/LANDOV
Pallbearers carry Campbell's casket after a funeral service in Medford, Massachusetts, on April 22, 2013.
Pallbearers carry Campbell's casket after a funeral service in Medford, Massachusetts, on April 22, 2013.
Kevork Djansezian/Getty Images
Mourners walk out of St. Joseph Catholic Church after Campbell's funeral service.
Mourners walk out of St. Joseph Catholic Church after Campbell's funeral service.
Kevork Djansezian/Getty Images
Nurse practitioner Maureen Quaranto, who treated victims of the bombings, wears her Boston Marathon jacket during Mass on April 21, 2013.
Nurse practitioner Maureen Quaranto, who treated victims of the bombings, wears her Boston Marathon jacket during Mass on April 21, 2013.
Mario Tama/Getty Images
From left, Boston Police Department Superintendents Kevin Buckley and William Evans attend Mass with Police Commissioner Edward Davis on April 21, 2013.
From left, Boston Police Department Superintendents Kevin Buckley and William Evans attend Mass with Police Commissioner Edward Davis on April 21, 2013.
Mario Tama/Getty Images
Photos of the deceased are displayed in Boston at the Cathedral of the Holy Cross on April 21, 2013.
Photos of the deceased are displayed in Boston at the Cathedral of the Holy Cross on April 21, 2013.
Mario Tama/Getty Images
Leaders of an interfaith service participate in a vigil near the finish line on April 21, 2013.
Leaders of an interfaith service participate in a vigil near the finish line on April 21, 2013.
MICHAEL REYNOLDS/EPA/LANDOV
A makeshift memorial honors the bombing victims on April 21, 2013.
A makeshift memorial honors the bombing victims on April 21, 2013.
Nicholas Czarnecki/Barcroft Media /Landov
Nicole Collier Lynch, Collier's sister, hugs a police officer during a vigil in Wilmington, Massachusetts, on April 20, 2013.
Nicole Collier Lynch, Collier's sister, hugs a police officer during a vigil in Wilmington, Massachusetts, on April 20, 2013.
DOMINICK REUTER/Reuters/LANDOV
People gather at a makeshift memorial in Boston on April 20, 2013.
People gather at a makeshift memorial in Boston on April 20, 2013.
Mario Tama/Getty Images
Huntsville, Alabama, residents hold a prayer vigil on April 19, 2013.
Huntsville, Alabama, residents hold a prayer vigil on April 19, 2013.
AL.COM /Landov
A man rings a bell at the vigil in Huntsville.
A man rings a bell at the vigil in Huntsville.
AL.COM /Landov
Two women embrace during a candlelight vigil in Somerville, Massachusetts, on April 18, 2013.
Two women embrace during a candlelight vigil in Somerville, Massachusetts, on April 18, 2013.
JESSICA RINALDI/Reuters/Landov
Obama talks with staff members at Massachusetts General Hospital while visiting injured patients on April 18, 2013.
Obama talks with staff members at Massachusetts General Hospital while visiting injured patients on April 18, 2013.
Official White House Photo by Pete Souza
A man at a Boston restaurant watches Obama speak on television on April 18, 2013.
A man at a Boston restaurant watches Obama speak on television on April 18, 2013.
STAN HONDA/AFP/Getty Images)
Mourners fill a Boston cathedral for an interfaith service on April 18, 2013.
Mourners fill a Boston cathedral for an interfaith service on April 18, 2013.
JEWEL SAMAD/AFP/Getty Images
Obama, first lady Michelle Obama and Massachusetts Gov. Deval Patrick attend the interfaith prayer service.
Obama, first lady Michelle Obama and Massachusetts Gov. Deval Patrick attend the interfaith prayer service.
Spencer Platt/Getty Images
Flowers, running shoes and other items are left in memory of bombing victim Lingzi Lu.
Flowers, running shoes and other items are left in memory of bombing victim Lingzi Lu.
Jared Wickerham/Getty Images
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.
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.
JESSICA RINALDI/Reuters/LANDOV
Danielle Cerroni writes a chalk message on the street near the marathon's finish line on April 17, 2013.
Danielle Cerroni writes a chalk message on the street near the marathon's finish line on April 17, 2013.
Spencer Platt/Getty Images
A woman looks at memorials left at the scene of the attack.
A woman looks at memorials left at the scene of the attack.
Spencer Platt/Getty Images
A crowd gathers at Boston's Garvey Park during a vigil for bombing victim Martin Richard on April 16, 2013.
A crowd gathers at Boston's Garvey Park during a vigil for bombing victim Martin Richard on April 16, 2013.
Jared Wickerham/Getty Images
A woman uses her hand to keep wind from her candle during an interfaith service in Boston on April 16, 2013.
A woman uses her hand to keep wind from her candle during an interfaith service in Boston on April 16, 2013.
STAN HONDA/AFP/Getty Images
Mourners gather on the edge of the pond for a candlelight vigil in Boston on April 16, 2013.
Mourners gather on the edge of the pond for a candlelight vigil in Boston on April 16, 2013.
DON EMMERT/AFP/Getty Images
Students from the Clifden Academy hold an American flag and candles during a vigil in Dorcester, Massachusetts, on April 16, 2013.
Students from the Clifden Academy hold an American flag and candles during a vigil in Dorcester, Massachusetts, on April 16, 2013.
JOHN MOTTERN/AFP/Getty Images
People walk along the barricade at Boylston Street on April 16, 2013.
People walk along the barricade at Boylston Street on April 16, 2013.
Darren McCollester/Getty Images
Mourners in Boston hug one another during a vigil for victims on April 16, 2013.
Mourners in Boston hug one another during a vigil for victims on April 16, 2013.
Spencer Platt/Getty Images
Five-time Boston Marathon runner Jose Sotolongo, center, reacts during a moment of silence in Miami on April 16, 2013.
Five-time Boston Marathon runner Jose Sotolongo, center, reacts during a moment of silence in Miami on April 16, 2013.
Joe Raedle/Getty Images
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.
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.
Bruce Bennett/Getty Images
Members of the Boston Red Sox observe a moment of silence before their Major League Baseball game in Cleveland on April 16, 2013.
Members of the Boston Red Sox observe a moment of silence before their Major League Baseball game in Cleveland on April 16, 2013.
Jason Miller/Getty Images
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.
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.
SHANNON STAPLETON/Reuters/LANDOV
Two young girls leave flowers on the steps outside the Boston home of 8-year-old bombing victim Martin Richard on April 16, 2013.
Two young girls leave flowers on the steps outside the Boston home of 8-year-old bombing victim Martin Richard on April 16, 2013.
CJ GUNTHER/EPA/LANDOV
Traders at the New York Stock Exchange observe a moment of silence before the opening bell on April 16, 2013.
Traders at the New York Stock Exchange observe a moment of silence before the opening bell on April 16, 2013.
BRENDAN MCDERMID/Reuters/LANDOV
The flag above the White House flies at half-staff on April 16, 2013.
The flag above the White House flies at half-staff on April 16, 2013.
MANDEL NGAN/AFP/Getty Images
The Minnesota Twins stand during the national anthem before a baseball game in Minneapolis on April 15, 2013.
The Minnesota Twins stand during the national anthem before a baseball game in Minneapolis on April 15, 2013.
Hannah Foslien/Getty Images
Obama makes a statement about the bombings on April 15, 2013.
Obama makes a statement about the bombings on April 15, 2013.
Win McNamee/Getty Images
Players and fans observe a moment of silence before an NBA game in Oakland, California, on Aprl 15, 2013.
Players and fans observe a moment of silence before an NBA game in Oakland, California, on Aprl 15, 2013.
JOHN G. MABANGLO/EPA/LANDOV
An American flag flies at half-staff at the Capitol building in Washington on April 15, 2013.
An American flag flies at half-staff at the Capitol building in Washington on April 15, 2013.
Alex Wong/Getty Images
Hockey fans in Glendale, Arizona, pause for a moment of silence before a game on April 15, 2013.
Hockey fans in Glendale, Arizona, pause for a moment of silence before a game on April 15, 2013.
Christian Petersen/Getty Images