After shooting buffalo videos, social platforms are faced with questions

“It’s spreading like a virus,” Ms Hochul said, urging social media executives to evaluate their policies to ensure that “everything possible is being done to ensure that this information is not spread.”

There may not be easy answers. Platforms such as Facebook, Twitch and Twitter have made progress in recent years, experts said, in removing violent content and videos faster. Following the New Zealand shooting, social platforms and countries around the world joined an initiative called the Christchurch Call to Action and agreed to work closely together to combat terrorism and violent extremism. One tool that social sites have used is a shared database of hashes or digital fingerprints of images that can tag inappropriate content and remove it quickly.

But in this case, Ms. Duek said, Facebook seems to have failed despite the hash system. Facebook posts that link to the video posted on Streamable have generated more than 43,000 interactions, according to CrowdTangle, a web analytics tool, and some posts have been posted for more than nine hours.

When users tried to label content as violating Facebook’s rules, which do not allow content that “glorifies violence”, in some cases they were told that the links were not contrary to Facebook’s policies, according to screenshots viewed by The New York Times.

Since then, Facebook has begun removing posts with links to the video, and a Facebook spokesman said the posts violated the platform’s rules. Asked why some users have been informed that posts with links to the video do not violate its standards, the speaker did not answer.

Twitter hadn’t removed many posts linking to the video, and in a few cases the video was uploaded directly to the platform. A company spokesman initially said the site could remove some copies of the video or add a sensitive content alert, then later said Twitter would remove all videos related to the attack after The Times requested clarification.

A spokesman for Hopin, Streamable’s video conferencing service, said the platform was working to remove the video and delete the accounts of people who uploaded it.