Hong Kong's protesters have hardened their resistance - now some want a revolution

Siobhan Robbins, South East Asia correspondent

Once again Hong Kong's air is thick with tear gas.

Angry and determined, it's protesters versus police in what is now a familiar game of cat and mouse.

After hundreds of thousands peacefully marched in the day, when night fell fresh clashes again broke out .

Officers with shields, rubber bullets, pepper spray and tear gas spent hours slowly clearing crowds of angry, young demonstrators after they blockaded the China Liaison Office.

Wave after wave, the tear gas and pepper spray came in, choking and temporarily blinding everyone in its path.

As police lines moved forward, we saw protesters throw bottles and paint as well as smouldering pellets that left your eyes watering.

Almost two months of demonstrations have hardened this resistance and strengthened their resolve, everyone I asked said they won't give up until their demands are met.

And that list of demands has lengthened and evolved, a battle against an extradition bill has now, for some, become a fight for full democracy- freedom from a Beijing-backed government.

Among the chants, they shouted "liberate Hong Kong" - some are now calling for revolution.

The action started earlier in the evening when groups barricaded roads, trapping people in their cars.

A few in the crowd turned, attacking a driver when he tried to push back before they were shouted down and restrained by their peers.

But others who were stranded in their cars said it was a worrying change in tone.

The government has again condemned the violence, criticising those in the pro-democracy camp, but also pro-government groups who attacked commuters in northern Hong Kong.

But condemnation will not cow the opposition and with no solution in sight this cycle will keep repeating.

The clashes with authorities are now becoming an almost weekly occurrence for a minority and they will not back down, they will not stop as some firmly believe this is their last chance to save this city.