Orlando massacre triggers first ever US Safety Check feature on Facebook

Facebook’s feature, which allows people to check on their friends in an emergency, was turned on for America for the first time after the mass killing in Orlando, which claimed 49 lives and left 53 injured.

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Safety Check allows people, who find themselves near a disaster area, to tell their friends that they are OK and check on them too. The idea is that regular communications during disasters may be disrupted, while social media offer a fast and reliable way to spread information.

It was inspired by the wide use of social media in Japan in the aftermath of the 2011 earthquake and tsunami. The first major disaster, in which the feature was used was in 2015 when a major quake hit Nepal. Last year, the feature was turned on after terrorist attacks in Paris, Brussels, Lahor and Ankara.

The Sunday massacre was the first event in the US, for which Safety Check was activated.

The mass shooting at a gay nightclub in Orlando was the deadliest incident of gun violence in the US and the third-deadliest case of single-perpetrator mass murder in history. Omar Mateen, 29, a US citizen of Afghan origin, was identified as the killer by the police, A SWAT team killed him in an operation to rescue hostages.