An indoor area in Hong Kong Polytechnic University is seen littered with metal barricades, bricks, and other big objects and assorted trash, in the morning of Nov 18, 2019. (Photos: China Daily)

Bottles and tins of chemical products, a cooking gas cylinder and assorted trash are seen lying on the ground of an indoor area in the Hong Kong Polytechnic University. In the morning of Nov 18, 2019.

A street in Hong Kong Polytechnic University is seen blocked by a few road barriers set up by protesters. In the morning of Nov 18, 2019.

A waiting area of a health clinic in the Hong Kong Polytechnic University is seen littered with used tissue, a broken umbrella and assorted trash. On Nov 18, 2019.

Two radicals dozing in an indoor area at the Hong Kong Polytechnic University, in the morning on Nov 18, 2019.