Hong Kong police show rioters damaging a restaurant at a press briefing on Dec. 16, 2019 in Hong Kong, south China. (Xinhua)

Hong Kong police said Monday that students accounted for more than half of the people arrested during the violent incidents that happened on Sunday.

There were 17 students among a total of 31 arrests made on Sunday, Hong Kong police said at a press conference.

Concerns have been on the rise as an increasing number of young people, in particular students, were involved in violent incidents. Since June 9, the police have arrested in total 6,105 people, in which almost 40 percent were students.

The police warned against the acts of exploiting or inciting young students to participate in illegal and violent activities.

Rioters started disruptive activities on Sunday afternoon, vandalizing shops and restaurants and smashing glass walls at New Town Plaza in Shatin, and hurling a smoke bomb at a bus terminus. A female bystander was confined and assaulted by a group of masked rioters who demanded to inspect her mobile phone.

Violent acts escalated in Mong Kok at night as rioters blocked roads, set debris ablaze, attacked police officers with bricks, and threw traffic cones and trash at a police vehicle. 

Hong Kong police say they have made 6,105 arrests and prosecuted 978 people since June at a press briefing on Dec. 16, 2019 in Hong Kong, south China. (Xinhua)

Chief Superintendent of Police Public Relations Branch Kwok Ka-chuen said rioters have caused extensive damage to almost every single district across Hong Kong since October as altogether 897 locations have suffered varying degrees of damage.

In face of escalated violence, the police used the minimum force necessary in dispersal operation, he added.

Kwok stressed that the police had no choice but adopted appropriate forces after rioters committed violent acts and jeopardized the rule of law.

Over the past week, the police arrested 72 males and 27 females, aged between 12 and 54, for offenses including unlawful assembly and wounding. Eight police officers were injured during operations.

Besides, three people arrested for testing explosives were charged with two offenses including the manufacture of explosives on Monday, and their pleas for bail were rejected.

Since June, the police have made 6,105 arrests and prosecuted 978 people.