Facebook's Safety Check feature sparked a false bomb scare late on Tuesday, triggering fear and anger in the Thai capital.

The social network's feature is designed so that when a disaster or act of violence occurs, users may check-in to let their loved ones know they are safe. However, the algorithm backfired on Tuesday when a protestor throwing small explosives in front of a government building became "The Explosion in Bangok" - which the social media giant said had been confirmed by "multiple sources."

Although the incident had been covered briefly in the local press, the Facebook alert linked to a BBC article about the deadly 2015 bombing at the Erawan Shrine in Bangkok, causing more confusion.

Facebook stands by algorithm

Many citizens marked themselves as safe before the alert was deactivated around 10 p.m. local time (1500 UTC). Although many Thai users called on Facebook to apologize or alter their algorithm, the platform responded by defending its methods.

"Safety Check was activated today in Thailand following an explosion. As with all Safety Check activations, Facebook relies on a trusted third party to first confirm the incident and then on the community to use the tool and share with friends and family,” a spokesperson told the news website The Verge.

This is far from the first time Safety Check has stirred controversy. Last March, a bug sent a security notification to users all around the world after a fatal suicide bombing in Pakistan. Facebook has also been slammed for turning the feature on selectively - for example, during terrorist attacks in Paris but not in Beirut.

According to English-language Thai news outlet "Khaosod," police were weighing whether or not to prosecute Facebook for computer crimes and accused the social media site of spreading panic.

es/sms (AFP, dpa)