Image copyright AFP Image caption Ken Tsang was assaulted while taking part in 2014's pro-democracy protests

Seven police officers in Hong Kong have been convicted of beating a protester during pro-democracy rallies in 2014.

The group, charged with intentionally inflicting grievous bodily harm, were found guilty of a lesser charge of causing bodily harm.

Hong Kong saw major protests in 2014 after China ruled out open nominations for the election of its leader.

TV cameras caught the officers kicking and punching Ken Tsang, who was handcuffed, in a nearby park.

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The court found that two of the officers convicted did not directly take part in the assault, but Judge David Dufton said that "every police officer has a duty to prevent the commission of a crime", even if committed by fellow officers.

The ruling said Mr Tsang suffered injuries to his face, neck and body, but that these did not amount to "grievous bodily harm".

Image copyright Reuters Image caption A video filmed by the Apple Daily newspaper appeared to show officers beating a handcuffed protester, later identified as Ken Tsang

The police officers could face up to three years in jail. One officer was also convicted of assault for slapping Mr Tsang twice later on at a police station.

Defence lawyer Lawrence Lok had argued that the protests had affected police morale, saying that one of the officers who watched the violence had been physically and verbally abused by protesters.

"Human frailties resulted in the transgression of seven police officers," he said.

Last year Mr Tsang was found guilty of assaulting and resisting officers on the same evening. He splashed an unknown liquid on police and was handed a five-week sentence.

Image copyright EPA Image caption Supporters of Hong Kong's police gathered outside Wan Chai District Court

Police in Hong Kong are generally well-respected and incidents of violence are rare. Mr Tsang's beating caused public outrage amid the pro-democracy rallies.

The 2014 protests saw 79 days of student-led demonstrations and street occupations by protesters seeking fully free elections for Hong Kong's leaders.

Hong Kong has been part of China since 1997 but enjoys a high degree of autonomy under a principle of "one country, two systems".

But many Hong Kong locals are concerned about what they see as growing Chinese influence in the city's affairs, with some activists even calling for independence from China.

A date for sentencing has not been set.