HONG KONG - Amnesty International on Friday warned Hong Kong police against "excessive force" ahead of a planned rally by pro-democracy demonstrators, following scuffles as a major protest site was cleared earlier this week.
Police fired "pepper water" at crowds as they tore down tents and barricades in the busy commercial neighbourhood of Mongkok - home to one of three protest camps blocking major junctions in the semi-autonomous Chinese city - and made more than 140 arrests.
Amnesty said the two-day operation had seen "unjustifiable force against protesters, bystanders and journalists".
"The heavy-handed approach by police violates the protesters' rights to freedom of expression and peaceful assembly, and risks exacerbating an already tense situation," said Mabel Au, director of Amnesty International Hong Kong.
Footage from local news channel Digital Broadcasting Corporation showed a police officer hitting an unarmed man on the back with a baton near the cleared protest zone on Wednesday night.
Police spokesman Hui Chun-tak said Friday that the force was "highly concerned about a police officer suspected in an incident of unnecessary use of force" during the operation.
The force has initiated "follow-up action" and the officer has stopped participating in "related operations", Hui added.
Fresh scuffles broke out in Mongkok late Friday as thousands of protesters faced off against police, who surged through crowds with batons.
Police also deployed pepper spray as scores of officers pushed back protesters, telling them to disperse. But the crowd appeared to be in no mood to relent.
Friday marks exactly two months of mass street rallies in Hong Kong by protesters calling for free leadership elections in 2017. The Chinese government says the candidates must be vetted by a loyalist committee, which demonstrators say will result in the election of a pro-Beijing stooge.
Student leaders Joshua Wong and Lester Shum have accused police of using violence against them during their arrests on Wednesday as authorities clashed with demonstrators in Mongkok.
"They used fists to punch and feet to kick my body," said Shum, who was released on bail late Thursday.
"They used their knees... and kicked me in the waist."
In a separate case, seven officers were arrested Wednesday over a video that had emerged of police beating and kicking a handcuffed protester in October.
Protest leaders have announced plans for a large-scale rally at the main protest in central Hong Kong on Sunday.
But Hui said that the planned rally was "illegal" and urged protesters to leave the occupied roads.
The protests have at times drawn tens of thousands of people onto the streets, but the crowds have dwindled as the movement struggles to maintain momentum and commuters grow weary of transport disruptions.