Hong Kong's most prominent student activist Joshua Wong has called for the resignation of leader Carrie Lam, after walking free from prison.
Wong, 22, became the face of the 2014 pro-democracy protests which called for the city to pick its own leaders.
People in Hong Kong are again out on the streets, this time against a controversial bill which allows extradition to mainland China.
Observers say Wong will further rally crowds and increase pressure on Ms Lam.
Organisers say more than two million people rallied against it on Sunday, despite the bill being suspended by Ms Lam on Saturday. The police put the figure at 338,000.
Critics have said the legislation would expose people in Hong Kong to China's deeply flawed justice system and lead to further erosion of the city's judicial independence.
Much of the public anger has been directed at Ms Lam, who is pro-Beijing, and on Sunday she apologised for the controversy over the bill.
After diminishing in numbers overnight, large groups of protesters were seen gathering on key roads near the government headquarters again on Monday. Organisers say protests will continue until the bill is scrapped altogether.
Wong, who received two separate prison sentences in 2017 and 2018 for his part in what became known as the Umbrella Movement, walked free on Monday after serving a reduced sentence of one month.
"[Carrie Lam] is no longer qualified to be Hong Kong's leader," Wong told reporters at the prison. "She must take the blame and resign, be held accountable and step down."
He also celebrated his new found freedom and called for the extradition bill to be withdrawn in a tweet on Monday.
The recent wave of protests in Hong Kong are reminiscent of the Umbrella Movement that took place in 2014.
The protests started in reaction to a decision made by China that it would allow direct elections in Hong Kong in 2017, but only from a list of candidates pre-approved by Beijing.
Wong and other student activists led the protests which saw thousands of people camp in the central business district for 79 days, bringing the city to a standstill.
The student activists were later convicted of unlawful assembly and jailed over an incident that helped trigger the mass protests.
Four other pro-democracy activists, including university professors and a Baptist minister, also received sentences for their part in the protests.
BDST: 1218 HRS, JUNE 17, 2019