A human rights activist nicknamed ‘Super Vulgar Butcher’ has been jailed in China for eight years for “subversion” – the harshest sentence given in a crackdown on activists that began in the country in 2015.

Wu Gan, a 44 year-old administrator at a Beijing law firm, campaigns for victims in criminal cases viewed as sensitive by authorities. He was sentenced at the Tianjin No 2 Intermediate People’s Court.

It is the longest sentence given so far in the ‘709 crackdown,' a sweep-up of hundreds of activists and lawyers that began two years ago. Mr Wu was accused of attempting to overthrow the ruling communist party.

He used the name ‘Super Vulgar Butcher’ on social media, and raised awareness of cases involving members of the public caught up in legal cases against officials.

In 2009 he supported a pedicurist charged with killing a government official who attempted to molest her. He also campaigned for justice for the family of Xu Chunhe, who was killed by a police officer in the northeastern Heilongjiang province in 2015.