Obama: Shooting in Orlando Was 'Act of Terror' Politicians react to worst mass shooting in US history By Neal Colgrass, Newser Staff Posted Jun 12, 2016 2:31 PM CDT 534 comments Comments President Barack Obama speaks about the massacre at a Orlando nightclub during a news conference at the White House in Washington, Sunday, June 12, 2016. (AP Photo/Pablo Martinez Monsivais) (Newser) – President Obama says the mass slaughter that left at least 50 dead and 53 wounded at an Orlando LGBT nightclub on Sunday was an "act of terror," CNN reports. "We know enough to say this was an act of terror and an act of hate," he said in the White House briefing room. "The FBI is appropriately investigating this as an act of terror. We will go wherever the facts lead us ... What is clear is he was a person filled with hatred." Facts are just leaking out, but media outlets say the shooter—29-year-old Omar Mateen, who died at the scene—called 911 and pledged allegiance to ISIS before opening fire at the nightclub. What's more, ISIS claimed responsibility Sunday for the killings via its Amaq news agency, Reuters reports. Among other reactions: "Woke up to hear the devastating news from FL," tweeted Hillary Clinton. "As we wait for more information, my thoughts are with those affected by this horrific act." Donald Trump's tweets went from moderate to aggressive in a short span of time. "Police investigating possible terrorism," he wrote at first, but soon amped up to, "Is President Obama going to finally mention the words radical Islamic terrorism? If he doesn't he should immediately resign in disgrace!" Bernie Sanders pitched in with, "I believe that in this country, we should not be selling automatic weapons which are designed to kill people. We have got to do everything that we can on top of that to make sure that guns do not fall into the hands of people who should not have them." One story has it that a public, gay kiss sent Mateen into a rage.