The Hong Kong Police Force criticized on Monday what it called the violent acts of rioting mobs over the weekend, saying their behavior showed a clear intention to kill police officers.

The violence escalated from Friday to Sunday as rioters slashed an officer in the neck with a box cutter and detonated a homemade explosive device, for the first time, in an attempt to attack a police vehicle, police said.

Over the weekend, 201 people were arrested, including a 19-year-old student who was accused of slashing the officer in the neck on Sunday. The officer, who sustained a 3-to 4-centimeter long wound, remained in a hospital intensive care unit on Monday, police said in a media briefing. Surgeons repaired damage to a vein and nerve in his neck, police said.

The 19-year-old student was arrested on a charge of attempted murder, which carries a possible life sentence. Another person at the scene was arrested on undisclosed charges related to the attack, officials said.

Tang Ping-keung, deputy commissioner of police operations, said on Monday that violence in Hong Kong has escalated to a point that rioters are "aiming to take the lives of police officers".

The homemade bomb, remotely detonated with a mobile phone, exploded in a flower planter at the junction of Nathan Road and Fife Street in Mong Kok on Sunday, according to the superintendent of the Explosive Ordnance Disposal Bureau, Suryanto Chin-chiu. A nearby police vehicle was the apparently target of the attack, police said. It was not damaged.

Twelve police officers were injured during operations against the citywide violence and vandalism, said Kong Wing-cheung, acting chief superintendent of the Police Public Relations Branch.

Two police officers were assaulted with bricks, city officials said. No information was immediately available about the others' injuries.

Dozens of gasoline bombs were tossed at police targets, including a police vehicle and the Mong Kok Police Station.

Online posts have appeared calling for the murder of police officers. The posts, which were seen by reporters from China Daily and other media outlets, have included instructions on making gasoline bombs and where and how to stab officers.

Police officials have vowed resolute action to bring offenders to justice. They appealed to residents to distinguish fact from fiction amid what they called malicious online rumors against police officers.

In a written statement, a Hong Kong government spokesman expressed outrage at the continued violence, which the statement said has ruined the city's peace and order and jeopardized residents' personal safety.

"Radicals will never achieve their political demands by resorting to street violence," said Regina Ip Lau Suk-yee, chairwoman of the New People's Party, calling the targeting of police "shocking" and "unacceptable to a civilized society".

In a social media post, Leung Chun-ying, vice-chairman of the National Committee of the Chinese People's Political Consultative Conference and former chief executive of Hong Kong, urged opposition lawmakers to take a clear position against violence.

Lai Tung-kwok, former secretary for security, slammed the violence, which has brought life in the community to a standstill, and urged the city's residents to stand against the violence.

Legal experts from the Hong Kong Legal Exchange Foundation issued a statement saying that the rioters' acts have been premeditated, organized crimes that under the law could lead to life imprisonment for the perpetrators.

China Daily