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 would allow extradition to mainland China.
China has said it will continue to support Ms Lam.
Organisers say more than two million people rallied against the extradition bill on Sunday, despite it being suspended. 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 gathered near the government headquarters again on Monday.
Demonstrators are pushing for the bill to be scrapped completely, for those jailed during the protests to be freed and for the resignation of Ms Lam.
Who is Joshua Wong?
Wong left prison on Monday after being jailed in May on contempt charges related to his involvement in the pro-democracy protests known as the Umbrella Movement.
Speaking to the BBC he said he was ready to “join the fight” against the extradition bill, and called for Ms Lam to step aside.
“It’s time for her to end her political career,” he said, saying she had “allowed police to hold a gun to the citizens of Hong Kong”.
“It’s hard for us to accept that Carrie Lam, the leader of Hong Kong, copy the model of the Tiananmen Square massacre to such a modern global financial centre,” he added, referring to China’s bloody crackdown on pro-democracy protests in 1989.
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.
Why are people taking to the streets now?
Protesters fear the extradition bill could bring Hong Kong more decisively under China’s control.
On Sunday, organisers said two million turned out on the streets against the bill, which if confirmed would make it the largest protest in Hong Kong’s history.
The protest was mainly peaceful, with police officers reportedly holding back to allow the throngs of people to slowly pass through the city.
This is in contrast with scenes at the last major demonstration on Wednesday, which saw clashes between protesters and police that injured dozens.
Defending the bill. Hong Kong officials said its courts would have the final say as to whether to grant extradition requests.
Ms Lam’s government had also said suspects accused of political, religious and certain types of commercial crimes would not be extradited.
Hong Kong has been part of China since 1997 under the “one country, two systems” principle, which allows it freedoms not seen on mainland China.