Facebook has activated its "safety check" feature in the wake of the terror attacks in Paris on Friday.
The feature, which has previously been used in natural disasters, allows people in the affected areas to let Facebook friends know they are safe.
Users can also visit the safety check website to see which of their friends are in the area and who has checked in as safe.
The feature sends push notifications to Facebook users who have friends in the affected area, alerting them when friends have marked themselves as safe.
Facebook introduced the feature last year and CEO Mark Zuckerberg said it was inspired by the devastating earthquake that hit Japan in 2011.
Many on social media applauded the feature on Friday evening.
The social network previously activated the feature following the April 2015 earthquake in Nepal and earlier this year during Hurricane Patricia, which hit Mexico in October.