MELBOURNE, Australia (AP) — Australia's online safety watchdog has filed legal action against messaging app Telegram, saying the platform failed to remove extremist content including videos of white supremacist mass shootings in Buffalo, New York, and the New Zealand city of Christchurch as well as Islamic State group beheadings. "We reject these allegations and will contest them in court," a spokesperson said in a written statement sent on Telegram. "We allege that this content remained accessible on the service long after Telegram had been put on notice," she said. In Buffalo in 2022, an American white supremacist livestreamed on Twitch part of a shooting at a supermarket in which he killed 10 Black people. He cited among his motivations the crimes of an Australian white supremacist who in 2019 livestreamed on Facebook a shooting at two Christchurch mosques, where he murdered 51 Muslim worshippers.