Within 24 hours of the shootings in New Zealand mosques that left at least 50 people dead, Facebook removed or blocked 1.5 million videos of the attack, the company said Sunday.

The alleged gunman wore a helmet with a camera attached to it, and livestreamed the shootings on Facebook and Twitter. Facebook New Zealand spokeswoman Mia Garlick said that about 300,000 videos of the terror attack were removed from the social media site, and 1.2 million more were blocked at upload.

"Out of respect for the people affected by this tragedy and the concerns of local authorities, we're also removing all edited versions of the video that do not show graphic content," Garlick tweeted, adding that there are monitors working at all hours to keep videos off the platform.