Protesters clashed with police in the southern Chinese megacity of Guangzhou overnight Tuesday into Wednesday, according to witnesses and footage, part of a wave of demonstrations across the country triggered by Covid restrictions.

Security personnel in hazmat suits formed ranks shoulder-to-shoulder, taking cover under see-through riot shields, to make their way down a street in the southern city's Haizhu district as glass smashed around them, videos posted on social media showed.

In the footage -- geolocated by AFP -- people could be heard screaming and shouting, as orange and blue barricades were pictured strewn across the ground.

People are seen throwing objects at the police, and later nearly a dozen men are filmed being taken away with their hands bound with cable ties.

A Guangzhou resident surnamed Chen told AFP on Wednesday that he witnessed around 100 police officers converge on Houjiao village in Haizhu district and arrest at least three men on Tuesday night.

China's vast security apparatus has moved swiftly to smother protests across the country, as frustration over heavy-handed Covid rules bubbled after a fire in a locked down building in Urumqi in the northwestern Xinjiang region killed 10 people last week.

Haizhu, a district with more than 1.8 million people, has been the source of the bulk of Guangzhou's Covid-19 cases. Much of the area has been under lockdown since late October.

Earlier in November, protesters in Haizhu had crashed through lockdown barriers and marched onto streets in a rare outburst of public anger against Covid restrictions.

Videos of that protest circulated on social media on November 14, and verified by AFP, showed hundreds of people taking to the street in Haizhu. Some tore down barriers set up to keep locked-down residents from leaving their homes.

- 'Trembling and crying' -
Meanwhile, videos published on China's Twitter-like Weibo on Tuesday night showed long lines of traffic as residents rushed to leave the neighbouring Tianhe district.

One student who was told to leave her college dormitory said on Weibo: "I used to think this would be the happiest time of my life... Now I receive an emergency notification at 1:00 am, I end up trembling and crying in the corridor at 2:00 am, and I watch my classmates flee with suitcases at 3:00 am. At 4:00 am, I sit alone on my suitcase and cry, waiting for my parents to come...

"At 5:00 am, I finally got in the car and escaped from this man-eating place. I used to say that this land is kind ... now it's like hell," the writer who uses the pseudonym Ludao Lizi said on a verified Weibo account.

Zhang Yi, a spokeswoman for the Guangzhou National Health Commission on Tuesday said "the epidemic in Tianhe District is developing rapidly, and the risk of social transmission continues to increase".