Activist Joshua Wong, who was a poster child of Hong Kong's "Umbrella Movement" in 2014 for universal suffrage, was on Friday arrested by police along with two other activists, reports said.
Wong and two other prominent activists — Andy Chan and Agnes Chow — were detained ahead of the weekend protests, 12th in a row, which began against a now-withdrawn extradition bill and turned into a larger movement for greater autonomy and democracy, in the semi-autonomous region.
The 22-year-old activist was released from jail in June after serving five weeks in prison on charges of contempt of court.
He was the face of Hong Kong's push for the full democracy movement in 2014 that paralysed parts of the region, which enjoyed a greater autonomy, has separate judiciary and right to protest, under "one country, two systems" agreement following its handed over to China by Britain in 1997.
He inspired hundreds and thousands of people to come out on the streets for two months in 2014 in demand for full free elections. The Umbrella Movement was a reaction against restrictions from Beijing on how Hong Kongers choose their next leader.
The movement, however, failed to attract any concession from China and died down within a few months, but the activist was later hailed as one of the world's most influential figures by Time and Fortune magazines.
Wong's life as an activist began just at the age of 13 when he joined protests against China's plans for a high-speed rail link between Hong Kong and the mainland. He later campaigned against a pro-China "National Education" program, which was eventually dropped by Beijing.
Wong is also a founding member of political party Demosisto for more self-determination for Hong Kong, but not independence. Activists Nathan Law and Chow are other founders of the pro-democracy party, which demands that Hong Kongers should get to decide their city's fate, not Communist Party officials in Beijing.
Chow of Demosisto was last year disqualified from running for legislative elections because of her party's demand for self-determination, which Chinese authorities have interpreted as support for independence.
After his release from jail on June 17, Wong had said he was eager to join the protests, which are largely a leaderless movement, and called for Hong Kong Chief Executive Carrie Lam's resignation as she was no more "qualified" to be Hong Kong residents' leader.