After a gunman opened fire in an LGBT nightclub in Orlando, Florida, reactions from politicians, celebrities and organisations have been flooding in on social media. Both presumptive candidates in the upcoming US election tweeted thoughts and prayers with those affected.

Former US Secretary of State and presumptive Democratic candidate for President, Hillary Clinton, tweeted that she woke up to hear the "devastating news" and that her thoughts were with "those affected by this horrific act".

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Her presidential rival, presumptive Republican candidate, Donald Trump initially tweeted "really bad shooting in Orlando" with "possible terrorism" before then saying he was "praying for all victims & their families" and asked "when will we get tough smart and vigilant?" He later said that he appreciated "the congrats for being right on radical Islamic terrorism".

A gunman killed 50 people and injured 53 in a crowded gay nightclub in Orlando
A gunman killed 50 people and injured 53 in a crowded gay nightclub in Orlando, Florida, before being shot dead by police Reuters

In the UK, Prime Minister David Cameron tweeted that he was "horrified by the reports" and thought were with the victims and their families.

Florida senator, Marco Rubio, called the incident a "horrifying act of terror."

Signer, Boy George, tweeted that he was "heartbroken" at the news and that he prays "for this world to change."

Calls have been issued for people to donate blood and pictures have emerged of snaking lines out of Orlando blood banks. The Gay and Lesbian Alliance Against Defamation tweeted that there is a GoFundMe account started to support victims of the mass shooting that took at least 50 lives.