According to the news outlet, seven other opposition figures were also sentenced to up to 18 months on similar charges.
Lai, the founder of the popular newspaper Apple Daily and a vocal opponent of Beijing, was already sentenced to a year in prison this April over his involvement in similar anti-government protests that took place in August 2019.
The mass protests in Hong Kong started in June 2019 as a reaction to proposed amendments to the city's extradition laws, later growing into a full-blown movement against Beijing's authority. The protests were marked by escalating violence between the opposition and the city's law enforcement. In response to the protests, China adopted a new national security bill that bans separatist, subversive and terrorist activities, along with any form of foreign interference in Hong Kong.