Transcript for Backlash to Donald Trump's Tweet After Orlando Shooting

outside the white house. This happened last night. The white house in mourning over the senseless ma Sa Kerr of 50 people in Orlando. The candidates are speaking out. ABC's Jon Karl is at the white house with more on that. Good morning to you, Jon. Reporter: Good morning, Amy. Reactions from Donald Trump and Hillary Clinton were a study in contrast. Hillary Clinton denounced it as an act of terror, adding, quote, we need to keep guns like the ones used last night out of the hands of terrorists or other violent criminals. Donald Trump for his part used his statement to denounce the attack and then went after the secretary Clinton and president Obama. President Obama disgracely refused to even say the world radical Islam. For that reason alone he should stop down. And trump also put out a tweet just hours after the attack saying, quote, appreciate the congrats for being right on radical islamic terrorism. I don't want congrats. I want toughness and vigilance. As you can imagine, Amy, that tweet really set off quite a firestorm. It certainly did and George

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