Tens of thousands of people took to the streets of Hong Kong on Sunday to protest against the jailing of three young democracy activists, with many questioning the independence of the Chinese-ruled city's judiciary.

Last Thursday Joshua Wong, 20, Nathan Law, 24 and Alex Chow, 27, were jailed for six to eight months for unlawful assembly, dealing a blow to the youth-led push for universal suffrage and prompting accusations of political interference.

Thousands of people marched in hot summer weather to the Court of Final Appeal, carrying placards and banners denouncing the jailing of the activists.