HONG KONG: Thousands of Hong Kong university and school students swapped classes for democracy demonstrations on Monday.

The boycott follows a weekend marred by some of the worst violence since unrest escalated more than three months ago, with protesters burning barricades and throwing petrol bombs, and police retaliating with water cannon, tear gas and batons, Reuters reported.

Riot police on Monday patrolled the subway, known as the MTR, where some of the most violent clashes have erupted.