A pro-democracy protester told Wednesday how he was kicked and punched during mass rallies in 2014 as seven police officers stood trial over the attack, which was captured on film and beamed around the world.

Civic Party activist Ken Tsang testified for the first time in the much-anticipated trial which kicked off last week.

Ken Tsang arrives at court.

All seven accused officers have pleaded not guilty.

Video footage of the assault, filmed by local media near the city’s government headquarters, shocked residents and dented their faith in the usually trusted police force.

Police have been criticised for their heavy-handed treatment of protesters during the rallies, which brought parts of the city to a standstill for more than two months. The demonstrators were asking for fully free elections for their future leaders.

Tsang, 40, said he was “assaulted” by seven men after he was subdued by police at a rally.

“I was dumped to the ground, then I was kicked and punched. I curled up my body with my face facing towards the wall,” said Tsang, dressed in a suit and yellow tie.

“I sensed I was beaten with (a) hard object. Someone stepped on me…I was in great pain. The pain lasted for a long time,” he said through an interpreter as the seven defendants sat stern-faced.

Ken Tsang arrives at court.

Tsang was also shown video footage in which prosecution lawyers asked him to identify himself. In one clip, he was thrown to the floor before several men kicked him in a dimly-lit corner next to an electricity substation.

The seven police, including senior officers, are charged with causing grievous bodily harm with intent on Tsang, while one also faces an allegation of common assault.

They were suspended from duty after their arrests.

Tsang himself was sentenced to five weeks in prison for assaulting and resisting officers after he splashed liquid on police on the same night he was beaten.

Tsang has said the accusations against him were to distract attention from his case against the police.

Pro-police supporters gathered outside court, chanting “We support our police force” while several Tsang supporters carried yellow umbrellas, a symbol of the democratic movement.

Defence lawyers have said they will challenge the authenticity of the videos.

Footage captured by local network TVB and broadcast at the time showed a group of men hauling a handcuffed Tsang to a dark corner in a public park, where he was beaten.

One man stood over him punching him while three others were seen repeatedly kicking him.

Nearly 1,000 people were arrested during the rallies, with student leader Joshua Wong facing a verdict later this month.

He was acquitted Tuesday in another protest-related case.

The hearings come as tensions remain high in the semi-autonomous city, with fears growing that Beijing is tightening its grip.

Hong Kong was returned to China in 1997 under a “one country, two systems” agreement and enjoys much greater freedoms than in mainland China, but there are concerns those freedoms are being eroded.

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