Hong Kong police Thursday said rioting had caused an approved procession to end early on the first day of 2020. The force reiterated its resolve to curb violence and warned rioters not to stir up violence on New Year.

"Rioters took the peaceful procession as their cover and conducted illegal and violent acts," Chief Superintendent Kwok Ka-chuen told reporters. "On account of public safety, the procession had to be called off after communication between the police and organizers."

The New Year Day march started at around 2:30 p.m. on Wednesday and ended three hours later after rioters began to set fires and trash shops and banks along the designated route.

The march was initially planned to finish at 10 p.m.

"Police have always supported processions that are in peaceful and rational manners. Yesterday's procession was peaceful in the beginning. But after two hours several violent acts erupted," Senior Superintendent NG Lok-chun of (Operations) Hong Kong Island said at a briefing.

Between December 31, 2019, and January 1, 2020, police arrested 420 people for offenses including unlawful assembly and possession of offensive weapons.

Among those arrested, 207 are men and 113 are women. Kwok said they're aged between 12 and 81 and added that four officers were injured in the arrest operations over the past two days.

He stressed that nobody should be present at a riot scene, no matter what their excuse is.

"No one has the privilege to stay in a riot when police officers have given repeated warnings for people to leave. You can claim to be a first aider, a human rights observer, you name it. But this doesn't give you any exemption from the legal liability from taking part in a riot," said Kwok. 

His colleague Senior Superintendent Ng Lok-chun also noted that people will be released straight away if preliminary investigations find they have done nothing wrong, rebuking accusations that officers had abused their powers.