Violent scuffles broke out between police and protesters at an anti-parallel trader rally in Tuen Mun on Sunday, where over 100 people vented their anger at Chief Executive Leung Chun-ying for failing to make changes to the mainland visitor policy.
A week after similar action in Yuen Long led to clashes and arrests, protesters went to Sheung Shui and Tuen Mun. Despite an online call for protest, there was no demonstration in Sha Tin.
Police had to intervene in several confrontations and used their batons and a police dog to arrest protesters later in the day.
Earlier, protesters were seen shouting and kicking the baggage and trolleys of passers-by.
A gold shop and a number of pharmacies and other stores in Tuen Mun had to close temporarily because of the disruption.
Sheung Shui experienced few problems, although the mood of protesters turned angry when they arrived in Tuen Mun later. They marched from the MTR station into the V City shopping mall, then Tuen Mun Town Plaza. Some protesters rushed into a jewellery shop, Chow Sang Sang, and shouted at customers. Police removed the protesters and staff closed the store.
Later, protesters shouting, "Clamp down on parallel trading. Cancel multiple-entry permits", tried to block buses going to the Shenzhen Bay border crossing.
The protest turned violent around 7pm as police tried to disperse the crowd near the MTR station. Police wielded batons to arrest some protesters as water bottles were hurled. Three men and a woman, aged 13 to 21, were arrested for assaulting or obstructing police. One officer was injured, police said.
Some protesters later went to Tsim Sha Tsui, a favourite haunt of mainland shoppers, where there were more clashes with police near the Clock Tower. Two more people were arrested, police said.
Meanwhile, Shenzhen Mayor Xu Qin said in Beijing: "I believe policy arrangements for the border must be normal arrangements on a mutually beneficial, equal and mutually respectful basis, conducive to interaction of people and further deepening cooperation of both sides."
Leung said it was "not easy" to amend the policy as it required agreement "from the central and local governments". He stopped short of naming Shenzhen.