The social network's Safety Check feature allows users in the area to let their friends and family know they're OK.
Facebook 's Safety Check feature was switched on after at least two suicide bombers near Afghanistan's Kabul airport killed members of the US military and Afghan citizens on Thursday.
Safety Check allows Facebook users to mark themselves as safe during crises or disasters, such as shootings, terrorist attacks or earthquakes, letting their friends and family know they're alive. The feature is part of the social network's online hub for crisis response. A page for the attack in Kabul includes a way for people to offer or request help. It also features news stories. Facebook receives alerts from global crisis reporting agencies, and Safety Check gets activated when people in the area post about a crisis.
Pentagon Press Secretary John Kirby said on Twitter that one explosion struck near the Abbey Gate of the Kabul airport and at least one other blast took place at or close to the nearby Baron Hotel.
Capt. Bill Urban, a spokesman at Central Command, said the number of US service members who died increased to 13 and 18 were injured, according to the Associated Press.
The Wall Street Journal, citing an unnamed US official, reported that at least 90 Afghans died from the attack, but death toll estimates varied as new information poured in. Reuters reported that the Islamic State, which is opposed to the Taliban and the US, claimed responsibility for the attack.
Facebook's crisis response tools are another example of how the world's largest social network is responding after Taliban militants seized power in Afghanistan, prompting thousands of foreigners and Afghans to try to flee the country. The company also released a one-click tool so people in Afghanistan can lock their accounts to prevent people who aren't their friends from seeing posts on their timeline or sharing their profile photos.
Facebook didn't respond to a request for comment.
Users posting on the crisis response page for the attack in Kabul offered to donate blood and expressed sadness about the attack.
US President Joe Biden issued a warning to those responsible for the attack, which he attributed to an Islamic State affiliate. "To those who carried out this attack, as well as anyone wishes America harm, know this: We will not forgive. We will not forget. We will hunt you down and make you pay," he said during a press conference at the White House.