Fiery clashes erupted across the city, with security chief John Lee cautioning "unthinkable" consequences if the violence continued.
Authorities have shut down schools, rail links and several businesses in the Asian financial hub as a safety precaution.
On Tuesday night, hundreds of black-clad protesters tried to block riot police from entering the Chinese University of Hong Kong (CUHK) near Tai Po by hurling bricks and petrol bombs.

                                
                                        
            Man charged with 10 counts of attempted murder after knife attack on UK train
        
            Tanzania's Hassan sworn into office after deadly election violence
        
            Powerful 6.3 quake kills at least 20 in Afghanistan, hundreds injured
        
            Turkey set to call for action on Gaza as soon as possible, source says
        
                
                
                