Hong Kong went through a "cold" Christmas this year as resurgent protests targeting shopping malls ruined the festive atmosphere, dealing another blow to local businesses during the traditional peak tourism season.

Groups of blackclad rioters swarmed popular shopping malls across the city on Wednesday and Thursday, forcing many shops and restaurants to close early.

Chanting anti-government slogans, the masked protesters roamed the malls floor by floor, blocked the entrances of elevators, creating chaos and leaving Christmas revelers in panic.

The malls hit included Sogo in Causeway Bay, Langham Place in Mong Kok, Telford Plaza in Kowloon Bay, New Town Plaza in Sha Tin and Tai Po Mega Mall in Tai Po Market, all of which are popular among tourists and residents.

There was also mayhem on Christmas Eve as rioters smashed shops, set fires on the streets and clashed with police in shopping centers.

The protest violence resurged after a brief lull, battering the already strained economy and dashing hopes of a recovery after more than six months of social unrest, said lawmaker Yiu Si-wing, who represents the tourism sector in the Legislative Council.

He said this year's Christmas holidays have failed to create a stimulus effect on the local economy, which is rare in recent years.

Fearing possible chaos, many shopping malls had reduced Christmas decorations - a major attraction for revelers.

Many public events originally planned to celebrate the New Year, as well as next month's Spring Festival, were also canceled. They included the fireworks display scheduled for Jan 1 every year, and the night parade normally held on the first day of the Lunar New Year.

According to Yiu, there was no noticeable increase in the number of tourists coming to Hong Kong for the Christmas break, which means the effect on tourism-related industries, such as the hotel, retail and catering sectors, was limited.

He warned that the local economy could deteriorate if the violence continues, and urged protesters to help restore calm for the benefit of the community.

In an online post on Wednesday, Chief Executive Carrie Lam Cheng Yuet-ngor criticized the rioters as "reckless and selfish" by dampening the festive mood and undermining businesses.

She said many residents and tourists are disappointed that their Christmas holidays have been ruined.

She pledged that the government will do its utmost to uphold the law and restore peace in Hong Kong.