Hong Kong's biggest music festival, has been cancelled, organisers said on Friday, the highest-profile event so far to fall victim to the increasingly violent political unrest engulfing the city.

British folk-rock sensations Mumford & Sons and American star Halsey were among the headliners for the festival this year, which was scheduled for November 22-24.

"Due to the escalation of the crisis this week, and therefore the uncertainty this creates for the coming weeks, Clockenflap 2019 will be cancelled," the organisers said in a statement.

"Until this week we were fully committed to delivering the festival. Unfortunately, the situation has now made this impossible."

Pro-democracy protests have escalated in the past week with widespread travel chaos wrought by roadblocks and targeted vandalism of metro stations and lines.

Violent clashes between police and protesters have left parts of the city debris-strewn.

Last Friday, a 22-year-old student died from head injuries sustained during a fall as police skirmished with demonstrators. And on Thursday, a 70-year-old man died after being hit by a brick.

Clockenflap is an annual festival that takes place in front of Hong Kong's iconic harbour and attracts tens of thousands of fans.

It is the latest in a growing list of banned, cancelled or postponed events in Hong Kong's normally packed social calendar.

Hong Kong's annual pride parade due on Saturday was downgraded to a stationary rally after police banned the traditionally boisterous and colourful march.

The WTA Hong Kong Open, Oxfam's annual trail run fundraiser as well as concerts by acclaimed K-Pop acts and comedians have been pulled as the city reels from the protests.

(France24)