HK riot police clashes with protesters on the streets

Protesters in Hong Kong trampled a Chinese flag, vandalized two subway stations and set at least two street fires on Sunday, as pro-democracy demonstrations took a violent turn once again.

The day's action began peacefully, as protesters filled a shopping mall and, in a new twist, folded paper "origami" cranes that they tied onto a large rigging they assembled in the mall in the outlying Shatin district.

Some put a Chinese flag on the floor and took turns running over it, before defacing it and putting it in a dumpster outside, which they then pushed into a nearby river.Hong Kong's pro-democracy protests, now in their fourth month, have often descended into violence late in the day and at night. A hardcore group of protesters says the extreme actions are needed to get the government's attention. On Saturday, police used tear gas and rubber rounds against protesters who threw gasoline bombs toward them and set fires in streets.