The Hong Kong Special Administrative Region (SAR) government and local police denounced the illegal assemblies on Saturday, which spiraled into violence. Police clashed with radical protesters who hurled petrol bombs at government buildings and attacked law enforcers. The Hong Kong police said 40 people were arrested overnight.

Violent protesters vandalize govt buildings in HK, throw petrol bombs

The organizers of Saturday's mass demonstration, which was banned by the Hong Kong police over "public safety" concerns, still went ahead with their plan. The unlawful gathering began at 1 p.m. but things soon saw a turn for the worse.

In addition to attacking police with corrosive liquid and bricks and setting public properties ablaze, radicals paralyzed traffic by putting up barricades and damaging subway facilities.

"The fire at Hennessy Road was very fierce at one point, posing a serious danger," said the SAR government in a statement.

The SAR government severely condemned such acts, vowing to bring to justice those who've put innocent people's lives at stake.

The Hong Kong police also condemned the violence, pledging to take resolute enforcement actions to safeguard public safety in Hong Kong and bring all offenders to justice, said the police in a statement on Sunday.