TORONTO -- Facebook is reassuring users that it has not been secretly collecting video of them, saying it’s now fixed a “bug” in its app that turned iPhone cameras on in the background.

After users posted screen-recorded videos to Twitter showing that the camera activated when they opened a photo or rotated to landscape mode.

In a series of tweets on Tuesday, Facebook's vice president of integrity, Guy Rosen, acknowledged the glitch and said no content was recorded, stored or uploaded in any incident.

“We’ve confirmed that we didn't upload anything to (Facebook) due to this bug and that the camera didn’t capture anything since it was in preview mode,” he wrote.

A new, corrected version of the app was submitted to the App Store, Apple’s distribution platform for smartphone apps, and was “already rolling out” on Tuesday, he added.

The social media goliath, which recorded more than US$55 billion in revenue last year, has faced increasing scrutiny around privacy issues in recent years, including the Cambridge Analytica data scandal in user information was sold for political purposes. The company has long denied that it eavesdrops on users for ad-targeting purposes.