Two teenagers in Hong Kong, aged 16 and 17, have been charged on April 22 with the murder of an elderly 70-year-old man, who died following a protest clash between rival factions during the city's political unrest in 2019.

The elderly man, Luo Chang-qing, died in November when pro-democracy supporters and pro-government counter-protesters started throwing bricks at each other in the border town of Sheung Shui.

Luo died from a blow to the head.

Videos of the incident have been uploaded online, one of which can be seen here.

This happened in Sheung Shui & apparently a group of pro-#Beijing people clashed with anti-Govt protesters #HongKong #HongKongProtests pic.twitter.com/4EZJr5XOPz

— Damon Pang (@damon_pang) November 13, 2019

The elderly man had been filming a fight between the two sides on his mobile phone when he was struck, local media reported at the time.

Police said they had charged two boys for his murder.

This is despite them being minors.

The teens face up to life in prison if convicted.

"The two were jointly charged with murder, wounding with intent and rioting," a police spokesman told reporters.

Hong Kong's protests lasted seven straight months.

They were sparked after extradition was to be allowed to mainland China, and the movement gathered steam to become a popular revolt against the proposed policy.

More than 7,800 people have been arrested, with nearly 40 per cent of them being students.