Hong Kong's government reiterated that violence is not the solution after an unapproved march descended into chaos with police firing tear gas and water cannons after demonstrators lobbed Molotov cocktails at government buildings, blocked traffic and set fires.
The government in a statement late Sunday said violence would only harm the community and it was sincerely trying to solve problems.
Thousands of people, black-clad masked protesters alongside families with children, defied a police ban and peacefully marched 2 kilometers (1.2 miles) from the Causeway Bay shopping district to the central business district, making continuous calls for democratic reforms.
Police had turned down the march permit, but the demonstrators were undeterred, as they have been all summer.
Some protesters later burned Chinese flags and vandalized subway stations. Hundreds of them targeted the government office complex, throwing bricks and gasoline bombs through police barriers.
Police responded by firing volleys of tear gas and using water cannon trucks to spray chemical-laced water as well as blue liquid that helped them identify offenders. Protesters retreated but regrouped in cat-and-mouse battles lasting a few hours before calm returned.
The anti-government protests have taken place since June and increasingly have been marked by violence and clashes with police.
The movement was sparked by an extradition bill many Hong Kong residents see as an example of the territory's autonomy being eroded under Chinese rule.
The government's decision to withdraw the bill was seen by the protesters as too little, too late. Their demands have grown to calls for greater democracy and police accountability, and some of the more confrontational protesters defend violence as necessary since peaceful demonstrations haven't effected change.
More than 1,300 people have been arrested amid the increasing clashes between protesters and police.
The unrest has battered Hong Kong's economy, which was already reeling from the US-China trade war. It is also seen as an embarrassment to Beijing, which has accused foreign powers of fomenting the unrest.