Matthew Helms visits a makeshift memorial Tuesday, October 3, for the victims of <a href="index.php?page=&url=http%3A%2F%2Fwww.cnn.com%2F2017%2F10%2F02%2Fus%2Fgallery%2Flas-vegas-shooting%2Findex.html" target="_blank">Sunday night's mass shooting in Las Vegas.</a> Helms worked as a medic during the shooting, which was the deadliest in modern US history.
Matthew Helms visits a makeshift memorial Tuesday, October 3, for the victims of Sunday night's mass shooting in Las Vegas. Helms worked as a medic during the shooting, which was the deadliest in modern US history.
Drew Angerer/Getty Images
American flags stand at half-staff as the sun rises over Washington on October 3.
American flags stand at half-staff as the sun rises over Washington on October 3.
Manuel Balce Ceneta/AP
A man leaves flowers outside the US Embassy in Moscow on October 3.
A man leaves flowers outside the US Embassy in Moscow on October 3.
Mikhail Voskresenskiy/Sputnik via AP
Lindsay Cotterman rests her head on Shawna Pieruschka's shoulder as they attend a candlelight vigil at the University of Nevada, Las Vegas on Monday, October 2.
Lindsay Cotterman rests her head on Shawna Pieruschka's shoulder as they attend a candlelight vigil at the University of Nevada, Las Vegas on Monday, October 2.
ROBYN BECK/AFP/Getty Images
Mourners attend a vigil at the corner of Las Vegas Boulevard and Sahara Avenue on October 2.
Mourners attend a vigil at the corner of Las Vegas Boulevard and Sahara Avenue on October 2.
Drew Angerer/Getty Images
The lights of Paris' Eiffel Tower were switched off October 2 to pay tribute to the victims of the Las Vegas attacks and the victims of <a href="index.php?page=&url=http%3A%2F%2Fwww.cnn.com%2F2017%2F10%2F01%2Feurope%2Fmarseille-knife-attack-train-station%2Findex.html" target="_blank">a knife attack</a> in Marseille, France.
The lights of Paris' Eiffel Tower were switched off October 2 to pay tribute to the victims of the Las Vegas attacks and the victims of a knife attack in Marseille, France.
LUDOVIC MARIN/AFP/Getty Images
A Kansas City Chiefs fan holds up a sign during the "Monday Night Football" game between the Chiefs and the Washington Redskins.
A Kansas City Chiefs fan holds up a sign during the "Monday Night Football" game between the Chiefs and the Washington Redskins.
Jay Biggerstaff/USA TODAY Sports
The lights of the Empire State Building are dimmed in New York on October 2.
The lights of the Empire State Building are dimmed in New York on October 2.
Kathy Willens/AP
Country music star Keith Urban performs "Bridge Over Troubled Water" during a candlelight vigil in Nashville, Tennessee, on October 2.
Country music star Keith Urban performs "Bridge Over Troubled Water" during a candlelight vigil in Nashville, Tennessee, on October 2.
Rick Diamond/Getty Images
People gather for the Nashville vigil on October 2.
People gather for the Nashville vigil on October 2.
Joe Buglewicz/Getty Images
City Hall in Tel Aviv, Israel, is lit up like the American flag on October 2.
City Hall in Tel Aviv, Israel, is lit up like the American flag on October 2.
JACK GUEZ/AFP/Getty Images
New York University students attend a vigil on October 2.
New York University students attend a vigil on October 2.
JEWEL SAMAD/AFP/Getty Images
Rosa and Alan Duarte attend a vigil at Las Vegas' City Hall on October 2.
Rosa and Alan Duarte attend a vigil at Las Vegas' City Hall on October 2.
Gregory Bull/AP
From left, first lady Melania Trump, US President Donald Trump, Vice President Mike Pence and Pence's wife, Karen, take part in a moment of silence at the White House on October 2.
From left, first lady Melania Trump, US President Donald Trump, Vice President Mike Pence and Pence's wife, Karen, take part in a moment of silence at the White House on October 2.
MANDEL NGAN/AFP/Getty Images
President Trump makes a statement about the mass shooting on October 2. "In times such as these, I know we are searching for some kind of meaning in the chaos, some kind of light in the darkness," he said. "The answers do not come easy. But we can take solace knowing that even the darkest space can be brightened by a single light, and even the most terrible despair can be illuminated by a single ray of hope."
President Trump makes a statement about the mass shooting on October 2. "In times such as these, I know we are searching for some kind of meaning in the chaos, some kind of light in the darkness," he said. "The answers do not come easy. But we can take solace knowing that even the darkest space can be brightened by a single light, and even the most terrible despair can be illuminated by a single ray of hope."
Evan Vucci/AP
Former US Rep. Gabrielle Giffords -- accompanied by her husband, Mark Kelly -- turns to shake her fist at the Capitol during a news conference on October 2. Giffords, who was shot by a constituent in 2011, has been calling on Congress to do more to address gun violence.
Former US Rep. Gabrielle Giffords -- accompanied by her husband, Mark Kelly -- turns to shake her fist at the Capitol during a news conference on October 2. Giffords, who was shot by a constituent in 2011, has been calling on Congress to do more to address gun violence.
Bill Clark/CQ-Roll Call/Getty Images
A moment of silence is held at the Martin Luther King Jr. Memorial in Washington during an event honoring the 60th anniversary of King's essay, "Nonviolence and Racial Justice."
A moment of silence is held at the Martin Luther King Jr. Memorial in Washington during an event honoring the 60th anniversary of King's essay, "Nonviolence and Racial Justice."
MICHAEL REYNOLDS/EPA