Facebook's vice-president of integrity says the social media platform has fixed a bug that activated users' cameras while they were scrolling through the app on their iPhones.
Some users noticed their camera apps automatically opened as they used Facebook on their iPhones, with the video screen visible in a small gap when the display screen shifted slightly.
Privacy concerns were raised when users reported the glitch on social media.
One of the earliest complaints was made on November 2 by Twitter user Neo QA, who said it was "a little worrying".
Another user Joshua Maddox posted a similar complaint on Twitter on Sunday.
"Even if it's a bug it shows that they can access and keep the camera behind something," he wrote on Twitter.
"That's the part for me that's crazy."
He accused the social media platform of being able to "look into people's private lives".
"I'm not an iOS [developer], but hiding something like the camera open is a little funky if you ask me," he said.
Guy Rosen, Facebook's vice-president of integrity, responded, telling Mr Maddox it "sounds like a bug" and that his team was "looking into it" on Wednesday morning.
Hours later, he said the team had fixed the issue, which appeared to have been caused by the team correcting another bug.
"We recently discovered our iOS app incorrectly launched in landscape," Mr Rosen wrote on Twitter on Wednesday morning.
"In fixing that last week in v246 we inadvertently introduced a bug where the app partially navigates to the camera screen when a photo is tapped.
"We've confirmed that we didn't upload anything to FB due to this bug and that the camera didn't capture anything since it was in preview mode.
"We've submitted a fixed version to the App Store which is already rolling out."
