Crimes recorded in Hong Kong in the first half of 2020 increased by 27.9 percent year on year, attributable to violent incidents in the social unrest since last June, Hong Kong police said on Wednesday, warning that Hong Kong's stable law and order situation has been severely challenged by turmoil and social dissension.

A total of 32,345 crimes were recorded in Hong Kong in the first half of 2020, an increase of 7,050 cases or 27.9 percent compared with the same period of 2019, when Hong Kong's half-year crime statistics hit a record low since 1977, the police said in a press release.

There were 4,507 cases of violent crime in the first half of 2020, an increase of 537 cases or 13.5 percent year on year.

The police said the increase was attributable to crimes in the social unrest arising from the now-withdrawn ordinance amendments concerning fugitive transfers since last June. These crimes, including arson, criminal damage, offences against public order, possession of offensive weapons and possession of unlawful instrument, totaled a rise of 1,479 cases or 52.1 percent.

Among theses crimes, arson cases increased by 85.2 percent, offences against public order such as riots and unlawful assembly rose by 7.1 folds, and cases of possession of offensive weapons and possession of unlawful instrument increased by 53.1 percent and 5.3 folds respectively.

As the negative factors of the violent incidents in relation to the social unrest have not yet fully subsided, the disobedience to law among some members of public is growing, economy is worsening and community-wide mask wearing has enabled criminals to conceal their identities more easily, it is difficult to restore the law and order situation to the level before last June within a short period of time, the police said.

As of June 30, 2020, 9,216 persons were arrested in connection with incidents in the social unrest. Among them, 3,725, or 40.4 percent, were students.

According to the police, 1,972 persons have been prosecuted, and 653 of them have been prosecuted with riot related offences. Among them, 252 persons had to bear legal consequences, including 57 persons sentenced to imprisonment from two weeks to four years.

Since last June, protests have become increasingly violent. In November, a man was set into fire by rioters in Ma On Shan, and another man was killed by bricks hurled at his head by rioters in Sheung Shui, according to the police.

The situation further escalated when rioters "hijacked" the school campuses of the Chinese University of Hong Kong and the Hong Kong Polytechnic University in the same month. In the riots, the number of petrol bombs hurled and level of violence used by the rioters were unprecedented, the police said.

Moreover, there are extremely violent groups using genuine firearms and explosives intended to kill police officers or force the government to accede to their so-called "demands," the police said, adding that they have arrested 83 persons in connection with 15 explosives and five genuine firearms cases, and 32 of them have been prosecuted.

In order to prevent, suppress and impose punishment on criminal acts which endanger national security, the Law of the People's Republic of China on Safeguarding National Security in the Hong Kong Special Administrative Region has come into force starting from June 30, 2020.

With the establishment of the Nation Security Department of the Hong Kong Police Force on July 1, 2020, the police will stringently enforce the law and conduct investigation to ensure effective implementation of the law in Hong Kong, the police said.

"Since June last year, Hong Kong has been tormented by turmoil and social dissension for over a year, and the stable law and order situation that this city used to maintain has been severely challenged," the police said, calling for joining hands to fight violence and the COVID-19 pandemic.

"The police will continue to professionally discharge its duties to uphold the rule of law and maintain law and order as well as social stability," the police added.