KYIV, Oct 13 (Reuters) - Belarusians who subscribe to social media channels deemed "extremist" face up to seven years in prison under new proposals published by the authorities on Wednesday. Social media channels such as Telegram messenger were widely used during mass street protests against President Alexander Lukashenko last year both to coordinate demonstrations and share footage of a violent police crackdown. Some of the most well-known Telegram channels, including the NEXTA news outlet, were categorised as "extremist" after the protests began. NEXTA has nearly 1 million subscribers while the Telegram channel of the TUT.BY news portal, which was closed down by the authorities, has 500,000. The Belarusian directorate for fighting organised crime said in a statement that "subscribers to extremist Telegram channels and chats will be held criminally liable ... as members of an extremist group." More than a hundred Telegram channels and chats have been recognised as extremist in Belarus. Anyone reposting their material can already be fined or detained for up to 30 days. Protests erupted last year after a presidential election that Lukashenko"s opponents say was blatantly rigged to keep the veteran leader in power. Tens of thousands of people were detained and human rights activists say more than 800 people are now in jail as political prisoners since the protests. The authorities have recently launched reprisals against citizens who voice dissent online. Hundreds of people were detained and face prison terms for making disrespectful comments about a KGB officer who died in a shootout in Minsk last month. read more "Belarus" independent media are destroyed, many journalists are imprisoned, websites are blocked," exiled opposition figure Sviatlana Tsikhanouskaya wrote on Twitter. "Now the regime threatens with criminal persecution & up to 7 years in prison for a subscription to "extremist" Telegram channels, incl. of free media. The truth is banned in Belarus."