An injured TV journalist, center, is helped by his colleague and a riot policeman after being hit by a stone thrown by a protester onto his face during a clash at Mong Kok district in Hong Kong, China, Feb 9, 2016. [Photo/Agencies]

Hong Kong police arrested another person on Wednesday suspected of being involved in the Monday night Mongkok riot in Fanling, bringing to 64 the number of people jailed on suspicion of participating in the riot.

Ko Wing-man, secretary for Food and Health of the Hong Kong Special administrative region, said more than 130 people injured in the incident were hospitalized, among whom more than 90 are police personnel. He said 13 people were still receiving hospital treatment as of Wednesday night and were in stable condition.

John Tsang Chun-wah, financial secretary of Hong Kong, said: "What happened in Mongkok on the second day of the new year on the Chinese lunar calendar makes me very sad and very outraged. Such irrational actions have gone far beyond our rule-of-law base line and are unacceptable to society.

"I hope people will cooperate with the police force to bring these outlaws to justice as soon as possible," he added.

Many organizations handed in petition letters to police headquarters in Wan Chai and at the Mongkok police station on Wednesday, calling on police to enforce the law strictly and fairly. Additionally, gifts were provided to police representatives with wish cards and fruit baskets to offer comfort to the injured police officers and to praise their bravery in maintaining public security and order.

Some members of the Hong Kong Federation of Trade Unions, including Alice Mak Mei-kuen, a member of the Legislative Council of Hong Kong, visited the Hong Kong police headquarters on Wednesday to urge the police to deeply investigate the incident.

Xinhua contributed to this story.