Three posts to the suspect's Facebook page ― a video announcing his intent to commit a murder, a graphic video of the killing, and a live video of his confession ― stayed online for about two hours, the social network said.
"We disabled the suspect's account within 23 minutes of receiving the first report about the murder video, and two hours after receiving a report of any kind," the company said. "But we know we need to do better."
Facebook said it was reviewing its "reporting flows to be sure people can report videos and other material that violates standards as easily and quickly as possible." The company noted it is "constantly exploring" ways to harness advanced technologies, such as artificial intelligence, to stop the spread of videos that violate its standards.
The man police have accused in the Cleveland killing, Steve Stephens, 37, remains at large. He is wanted for aggravated murder in the killing of Robert Godwin Sr., who was walking home from a family Easter gathering.
Authorities widened the search into a nationwide manhunt on Monday.
"We will leave no stone unturned," Cleveland Police Chief Calvin Williams said at a press conference.
In 2015, a man posted videos to social media of himself shooting and killing reporter Alison Parker, 24, and cameraman Adam Ward, 27, while they were filming a live broadcast for Roanoke, Virginia, news station WDBJ.