Over 360 people were arrested on suspicion of attending unauthorized assemblies in Central, Causeway Bay and Mong Kok in the Hong Kong Special Administrative Region (HKSAR) on Wednesday, said Hong Kong police.

The illegal gathering started in the morning as lawmakers were expected to discuss a bill on the national anthem law at the Legislative Council in the SAR.

Police said they arrested around 180 people in Central and Causeway Bay, about 50 people in Admiralty and around 60 people in Mong Kok, for taking part in unauthorized assemblies.

Police stressed they respect residents' rights to express their opinions peacefully, but their views must be expressed in a legal way.

At least 16 people were arrested in the morning for suspected possession of offensive weapons and dangerous driving.

According to the police, around 1 p.m., protesters occupied the carriageways in the vicinity of Pedder Street, Central, causing serious obstruction to traffic.

Officers are taking resolute action to enforce the law and using the minimum necessary force, the police said.

Protesters are warned to stop blocking the road and leave as soon as possible.

Wednesday's illegal assemblies also came days after a draft decision on establishing and improving the legal system and enforcement mechanisms for the HKSAR to safeguard national security was submitted to the third session of the 13th National People's Congress (NPC) in Beijing.

Over 180 people were arrested on Sunday for suspected taking part in violent protests in the Wanchai and Causeway Bay areas. Most of them were suspected of illegal assembly, according to the police. 

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Hong Kong residents from all walks of life have started an activity of signing a petition to show support for the NPC's Hong Kong national security legislation. In three days, over 1.1 million signatures have been collected. 

Every country has the right and responsibility to legislate on its own security issues, said Hong Kong tycoon Li Ka-shing on Wednesday, calling on people not to over-interpret the move.

Hopefully, the legislation will ease the central government's concerns over Hong Kong and play a positive role in ensuring its long-term stability and development, he told media. 

Li also stressed that the SAR government is duty-bound to consolidate the confidence of Hong Kong people in "One Country, Two Systems" and strengthen the trust of the international community. 

"Hong Kong is in an atmosphere of political chaos and an unclear business environment," said his elder son, Victor Li Tzar Kuoi, who also expressed his hope that the legislation can stabilize the situation and restore social and economic activities in the region.