Three protesters from Hong Kong's radical youth opposition were jailed on Monday for taking part in a violent unrest, receiving the harshest sentences handed down to democracy activists since the city returned to Chinese rule in 1997.

Edward Leung, 27, one of the leaders of a movement advocating Hong Kong's independence from China, was jailed for six years for rioting and assaulting police in a 2016 overnight protest that turned violent. He was found guilty of rioting by a jury and had pleaded guilty to assaulting a police officer.

Two other activists, Lo Kin-man and Wong Ka-kui, were jailed for seven and 3 1/2 years respectively for rioting.