Crowds in a major Chinese city have clashed with white hazmat-suited riot police, footage on social media shows, as the biggest anti-government protests in decades continue over stringent zero-COVID policies. The clashes took place in Guangzhou on Tuesday night, according to posts online. In one video posted on Twitter, objects can be seen flying at dozens of riot police in all-white pandemic gear, holding shields over their heads, as they advance in formation over what appears to be torn-down lockdown barriers. Police are later seen escorting a group of people in handcuffs to an unknown location. Another clip shows people…