Facebook users in the Orlando area were given the option to mark themselves 鈥渟afe鈥 in the aftermath of a mass shooting at a gay nightclub.

At least after a gunman opened fire inside Orlando鈥檚 Pulse nightclub early Sunday. Officials say another 53 people are in hospital. The shooting has been described as the worst mass shooting in U.S. history.

Facebook activated the safety feature in hours following the deadly attack.

Facebook has allowed its users to use the safety notices in past tragedies, including the Paris attacks last November and the bombings carried out in Brussels earlier this year.