Facebook launched a review on Monday of how it handles violent videos and other objectionable material, saying it needed to do better after a video of a killing in Cleveland remained on its service for more than two hours on Sunday.

The world's largest social network plans to look for ways to make it easier for people to report videos and to speed up the process of reviewing items once they are reported, Justin Osofsky, Facebook's vice president for global operations and media partnerships, said in a blog post.

"We prioritize reports with serious safety implications for our community, and are working on making that review process go even faster," Mr Osofsky said.