San Francisco, Mar 20 (IANS): Technology companies, including Facebook and Twitter, have been asked to brief the US Congress on March 27 regarding their response to dissemination of the video of the New Zealand terrorists attack on their platforms.

In a letter to CEOs of Facebook, Twitter, YouTube and Microsoft, Chairman of the House Homeland Security Committee Bennie Thompson also warned them unless they do better in removing violent content, the Congress could consider policies to bar such content on social media.

Strapped with a GoPro camera to his head, the gunman broadcast graphic footage of the New Zealand shooting via Facebook Live for 17 minutes, which was later shared in millions on other social media platforms, including Twitter and YouTube.

Fifty people were killed and dozens injured in the shootings at Al Noor Mosque and the Linwood Avenue Masjid in Christchurch on March 15 after 28-year-old Australian Brenton Tarrant opened indiscriminate firings.

Facebook on Sunday said it had removed nearly 1.5 million videos of the attack in the first 24 hours.

Thompson slammed the tech giants for being slow in removing the terror content from their platforms despite calls from New Zealand authorities to take down those videos.