Tens of thousands of people thronged Hong Kong’s streets on Saturday to mark the fifth anniversary of the pro-democracy “umbrella movement” in protests that quickly turned violent, as pressure builds in the territory ahead of the 70th anniversary of the founding of the People’s Republic of China on Tuesday.

An evening that began with a peaceful rally descended into chaos, with police usingwater cannon and pepper spray to disperse crowds who hurled bricks at the windows of Hong Kong’s government offices and launched at least one Molotov cocktail.

Demonstrators gathered in Admiralty, the neighbourhood that saw the first skirmishes of the 2014 umbrella movement, which failed in its objective to bring about democratic reform. At a government-sanctioned rally in Tamar Park, veterans from that movement addressed a peaceful crowd.