Angry demonstrators spread out across Hong Kong on Tuesday, disrupting transportation and the central business district and setting fires on a college campus, while riot police officers sprayed tear gas and water cannons to try to stop them.

The clashes came a day after the nearly six-month-old protests turned particularly violent. On Monday, a police officer shot a protester at point-blank range, and a man who scolded protesters was set on fire. Both victims were in critical condition on Tuesday morning.

Protesters are calling for greater democracy and policy accountability and have not been satisfied by concessions made by Hong Kong’s chief executive, Carrie Lam.