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WASHINGTON, DC - JUNE 14: (AFP-OUT) US President Barack Obama speaks on the Orlando shooting at the Treasury Department after convening with his National Security Council on June 14, 2016 in Washington, DC. Obama directly attacked Donald Trump's proposal to ban Muslims from entering the United States. (Photo by Jim Lo Scalzo-Pool/Getty Images)
Pool/Getty Images North America/Getty Images
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The Orlando Police Department released this photo of Omar Mateen, the person identified as the shooter in the Orlando terror attack.
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Orlando Police officers direct family members away from a multiple shooting at a nightclub in Orlando, Fla., Sunday, June 12, 2016. A gunman opened fire at a nightclub in central Florida, and multiple people have been wounded, police said Sunday.
Phelan M. Ebenhack/AP
Orlando Police officers direct family members away from a multiple shooting at a nightclub in Orlando, Fla., Sunday, June 12, 2016. A gunman opened fire at a nightclub in central Florida, and multiple people have been wounded, police said Sunday.
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An image taken from Omar Mateen's Myspace page.  Law enforcement sources identified Mateen as the shooter in the Orlando terror attack.
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A shooting and multiple injuries were reported at Pulse nightclub in Orlando.
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December 16, 2012 -- The shooting at Newton killed 20 children and six adults. At the memorial service, President Obama also cited the deadly shootings at Oak Creek and Aurora. "In the coming weeks, I will use whatever power this office holds to engage my fellow citizens -- from law enforcement to mental health professionals to parents and educators -- in an effort aimed at preventing more tragedies like this," said the president.
MANDEL NGAN/AFP/Getty Images
December 16, 2012 -- The shooting at Newton killed 20 children and six adults. At the memorial service, President Obama also cited the deadly shootings at Oak Creek and Aurora. "In the coming weeks, I will use whatever power this office holds to engage my fellow citizens -- from law enforcement to mental health professionals to parents and educators -- in an effort aimed at preventing more tragedies like this," said the president.
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Handguns that were swapped for gift cards during a Los Angeles Police Department sponsored gun buyback event in Los Angeles, California on December 13, 2014.  The city held the event in three locations and the public were able safely and anonymously surrender firearms in exchange for $100 and $200 gift cards.    AFP PHOTO/MARK RALSTON        (Photo credit should read MARK RALSTON/AFP/Getty Images)
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Handguns that were swapped for gift cards during a Los Angeles Police Department sponsored gun buyback event in Los Angeles, California on December 13, 2014. The city held the event in three locations and the public were able safely and anonymously surrender firearms in exchange for $100 and $200 gift cards. AFP PHOTO/MARK RALSTON (Photo credit should read MARK RALSTON/AFP/Getty Images)
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