Cloud-based instant messaging service Telegram fights to avoid the bans placed by Apple, Google and Amazon Web Services (AWS) on social media site Parler by purging posts deemed to incite violence and break its content rules.

Based in Dubai, Telegram has historically been reluctant to moderate or ban its users. The attack on the U.S. Capitol on Jan.,  fanned by incendiary social media posts, have apparently forced Telegram to do an about face.

Some 15 extremist Telegram channels were recently banned for extremist content, according to NBC News. Telegram has also censored on several other channels or chatrooms for the same reason.

One of the deleted channels had hosted white supremacist content since it sprang up in June 2020. Users kept posting U.S. Army manuals with bomb-making and munitions-making information on the channel.

Telegram founder Pavel Durov, a Russian foe of Vladimir Putin, on Tuesday announced Telegram had passed 500 million monthly users. Telegram was the 8th most downloaded app worldwide in 2020. Parler users began migrating to Telegram after AWS cut-off Parler from its cloud hosting service on Jan. 10, following decision by Apple and Google to close their app stores to Parler.

Parler CEO and founder John Matze on Wednesday said the app might never come back online since no other provider wants to host it fearing backlash from Big Tech. Parler sued Amazon for removing the service.