Hong Kong pro-democracy activist Joshua Wong said he was arrested again Thursday for allegedly participating in an unauthorized assembly last October.
Wong tweeted that he was arrested when reporting to the semi-autonomous Chinese territory's Central Police Station.
He said he was also accused of violating a pre-coronavirus pandemic law banning the wearing of masks in public places on the pretext they obscure identity.
Wong was expected to leave the police station and address journalists later Thursday.
He rose to prominence as a student leader during the 2014 Umbrella Movement protests for universal suffrage, and is among a growing number of activists being charged for various relatively minor offences since Beijing imposed a sweeping national security law on the territory that has severely restricted political speech.
He played a low-key role in mostly leaderless and sometimes violent anti-government protests last year that led to Beijing imposing the security law. However, with Beijing's encouragement, Hong Kong authorities have been pursuing charges against major opposition figures for illegal assembly and other minor infractions in what some call a campaign to harass and intimidate.
