Candidates react to Orlando nightclub massacre

Hillary Clinton and Donald Trump responded Sunday to the mass shooting early Sunday at a Florida nightclub in which dozens were killed or wounded.

"Horrific incident in FL. Praying for all the victims & their families. When will this stop? When will we get tough, smart & vigilant?" tweeted Trump, the presumptive GOP presidential nominee.

Clinton, the likely Democratic nominee, posted on her Twitter feed: "Woke up to hear the devastating news from FL. As we wait for more information, my thoughts are with those affected by this horrific act. -- H"

Democratic presidential candidate Sen. Bernie Sanders, D-Vt., tweeted: "It's horrific. It's unthinkable."

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