The site is asking everyone it thinks is near the site of the explosion in the Pakistani city if they are safe, using the controversial but high-profile tool. But the location-based feature appears to have gone slightly awry, sending messages to people who have never been to Pakistan to check if they are safe.
The feature was activated after a blast in a park that killed at least 52 people, mostly women and children, according to officials. The explosion occurred in the parking area of Gulshan-e-Iqbal Park, a few metres away from children's swings.
The feature is being used to check whether people thought to be in the nearby area are safe.
"Are you OK?" a message being sent to users reads. "It looks like you're in the area affected by [the explosion]. Let friends know that you're safe."
But that same notification appears to be sent to people across the world. People in locations including the UK and US saw the message, despite not having been to Pakistan or having posted about it.
"We have activated Safety Check in Lahore,” said a Facebook spokesperson. “We apologise to anyone who mistakenly received a notification outside of Pakistan and are working to resolve the issue."
Facebook's Safety Check feature has drawn sustained criticism for only being turned on for high-profile Western disasters, and not for people in other locations. The company was also criticised after the Brussels attack last week for not having turned the feature on quickly enough, only activating it hours after the explosions were first reported.
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