Rioters who stormed Hong Kong's local legislature complex in the early hours of Wednesday were strongly condemned by the city's government, police and lawmakers.

The full extent of the damage at the Legislative Council complex was revealed early on Wednesday. Scattered outside the entrance were a great deal of smashed glass and panels, broken granite slabs and twisted trash bins. About two dozen protesters were still present.

A plan to charge the LegCo building emerged late on Tuesday evening, as dozens of masked activists told protesters at Admiralty they wanted to attack the legislature because it was reading a law to curb freedom of expression on the Internet.

Ironically, the law amendment under scrutiny in the legislature would exempt online satire from breaching copyright laws. It was drafted and proposed after consultation with netizen groups. And there was actually no such an agenda for LegCo meetings on Wednesday.

Dozens of activists launched the attack at the main entrance of LegCo around 1 am. They used crowd control barriers, slabs and trash bins to smash glass of the building. The police regained control of the crowd by using pepper spray. They then formed a protective cordon some 10 minutes later.

The arrival of more riot police sparked fresh clashes on the outskirts of the LegCo compound. Aggressive protesters - wearing helmets and covered in plastic - jabbed at police with their umbrellas. Others used flashlights to irritate the officers.

Pepper spray was used again and strong warnings were given for demonstrators to withdraw. The mob thinned out as dawn arrived, but legislators decided to cancel scheduled meetings on Wednesday. This was over safety concerns and to assess the damage done to the premises.

Six men, ages 18 to 24, were arrested for criminal damage and assaulting police officers. Further arrests are likely.

The police "very strongly condemned" the clashes, Superintendent Steve Hui Chun-tak told a Wednesday news conference.

He said that anyone who "breaches the peace" during an illegal assembly was liable to be charged with the offense of rioting. If convicted, they can be sentenced to 10 years in prison. Damaging property in a riot is a separate offense with a possible sentence of 14 years in prison.

Hui added that it was also unlawful in Hong Kong to obstruct lawmakers from attending a chamber meeting and to incite offenses on the Internet. He urged protesters to be wary of being incited and "used" by others.

The government, in a statement, strongly condemned the actions of "some violent radicals". A government spokesman urged the public to observe the law when expressing their views. The spokesman said the government would not tolerate any violent acts.

Police collect evidence left by protesters who broke the window of the Legislative Council on Wednesday. Parker Zheng / China Daily