Leung, 27, was among a generation of young political activists who emerged after 2014's failed nonviolent protests over Beijing's decision to restrict elections.

His sentence shows the hard line authorities are taking toward those advocating for more open politics in the former British colony.

The South China Morning Post reported that Lo Kin-man, charged alongside Leung, was sentenced to seven years on a conviction for rioting, while a third man, Wong Ka-kui, 27, was given a sentence of 3 ½ years.

The Feb. 8-9, 2016, outbreak of violence in the city's working-class Mong Kok district was the most serious opposition to local authorities in decades.