Figures from the Security Bureau show the police fired around 2,330 canisters of tear gas when officers clashed with protesters on November 12 at the Chinese University and elsewhere in Hong Kong. That's the highest number in a single day since the anti-extradition movement began in June.
In all, about 10,000 rounds of tear gas, 4,800 rubber bullets and 19 live rounds have been fired.
The Security Bureau also told lawmakers that so far 5,800 people had been arrested at about 900 protests, with about 920 people charged.
More than 1,200 complaints have been filed against the police. They are being investigated by a team of 26 officers, who didn't take part in the operations relating to the unrest.