Supported by a friend, a man weeps for victims of the mass shooting just a block from the scene in Orlando
Facebook activated its "Safety Check" function on Sunday for the first time in the United States after a gunman massacred 50 people at a nightclub in Orlando, Florida.
The Safety Check, first introduced in October 2014, allows Facebook users to spread the word that they are safe in wake of a natural disaster or a crisis, and allows searches for those who might be in the affected area.
"Waking up this morning, I was horrified to hear about the shooting in Orlando.
My thoughts and prayers are with the victims, their families and the LGBT community," said Facebook Chief Executive Mark Zuckerberg on his official account.