Facebook activated its "safety check" feature in Lahore, Pakistan, after a suicide bomber killed more than 70 people who had gathered in a city park to celebrate Easter.
When "safety check" is on, Facebook users in the immediate area of a disaster or an attack are alerted and asked to "check in" and let people know they're safe. But something went wrong.
A "bug," Facebook said, mistakenly sent messages to Facebook users who were nowhere near Lahore at the time of the attack.
According to social media postings from people who said they received these notices in error, versions of the "safety check" notice went out to quite a few people in the United States and Britain. In the comment thread of Facebook's note about the bug, there are reports of messages going to Australia and the Democratic Republic of Congo. It's not clear right now exactly how widespread the error was, however.
A reporter from the Toronto Star noted that the text version of the safety check feature mentioned an "explosion," but didn't specify exactly where, making the message seem just a bit more alarming.