As protesters tried to crash through the glass façade of the Legislative Council Complex in Hong Kong on Monday, an expletive caught the attention of 44-year-old Pastor Siu Yung Wong. The young man who uttered the word—a teenage demonstrator—declared he would kill himself as a form of protest. He then began to walk away, alone.

Alarmed, Wong followed him.

Tides of protesters dressed in black flooded the streets of Hong Kong for the second consecutive Sunday to protest the controversial extradition bill that could see residents sent to mainland China to stand trial.

According to organizers’ estimates, nearly two million people attended the march, making it the biggest protest in the city’s history with more than a quarter of the population participating. The police estimate a much lower turnout of 338,000.

HONG KONG—On Aug. 17, the Chinese government dropped all pretenses of allowing autonomy in Hong Kong by sentencing its first political prisoners in the former British colony: Joshua Wong, 20, Nathan Law, 24, and Alex Chow, 27, will serve six to eight months in prison for leading the 2014 pro-democracy Umbrella Movement protest.