Volunteers and supporters streaming towards Polytechnic University were fearful of what might befall the demonstrators

As hundreds of protesters were trapped inside a university on Monday night, besieged on all sides by riot police, thousands of Hongkongers rose up in protest, filling highways, public squares and bridges trying to get to them.

The streets of the city were turned into a war zone as protesters, alumni, volunteers and other supporters streamed toward Polytechnic University in Kowloon, where anti-government protesters have been under siege for more than 36 hours.

Hundreds trapped inside Polytechnic as demonstrators try to break campus siege

Hong Kong police have fought running battles with protesters trying to break a security cordon around a university in the city, firing teargas both at activists trying to escape the besieged campus and at crowds trying to reach it from outside.

Police have said the demonstrators inside Polytechnic University had no option but to come out and surrender.

Pro-democracy activists see move as effort by Beijing to intervene in HK’s affairs

On Saturday afternoon, a few dozen Chinese soldiers jogged out of their barracks in triple file line, wearing shorts and matching army green T-shirts. They cheerily joined a group of residents, clearing away road blocks set up by anti-government protesters, using brooms and plastic buckets.

One of the officers of the People’s Liberation Army (PLA), when asked by a local journalist what the group were doing, responded: “We volunteered! Stopping violence and ending chaos is our responsibility.” He shouted: “We are spreading positive energy!”

Chinese soldiers stationed in Hong Kong came out to clear streets on Saturday, which protesters had strewn with debris to slow down any police advances while they had been on the campus. People's Liberation Army soldiers joined the clean-up outside Hong Kong Baptist University, the site of clashes earlier in the week. They can only be deployed to help with disaster relief or to maintain public order if requested by the local government. The controversial move threatens to escalate already high tensions in the Chinese territory

• Hong Kong: Chinese troops deployed to help clear roadblocks
  

A student was shot by Hong Kong police on Monday, the third time a demonstrator has been hit with live ammunition. Police used teargas, pepper spray and firearms at multiple locations as demonstrators blocked roads, lit fires and hurled missiles. 

Later in the day, a man was doused in a flammable liquid and set on fire after arguing with protesters. Both the student and the man were said to be in a critical condition.

Another clip appeared to show a police officer on a motorbike driving at protesters.

• Hong Kong protests: man shot by police and burns victim in critical condition

Police fire at unarmed student and middle-aged man set on fire in day of violent clashes

Two people are in a critical condition in Hong Kong after another day of protests and violent clashes between anti-government protesters and police that left more than 60 people injured.

A police officer shot an unarmed 21-year-old male university student in the stomach as demonstrators attempted to disrupt the Monday morning rush hour as part of a day of planned protests and strikes.