Also this week, universities' campuses become the site of clashes between riot police and protesters, exacerbating public anger against authorities for the use of force.

NewsHour special correspondent Divya Gopalan has this report from Hong Kong.

Five demands!

Not one less!

Stand with Hong Kong!

This has been the scene every lunchtime since the week began, in an area considered to be Hong Kong's Wall Street.

Many office workers have joined the protest movement, which has gripped the city for nearly six months.

And once they leave, riot police take over, clearing strategically placed bricks on the road, trying to get the commercial heart of the city back to business.

An uneasy calm on Friday caps off one of the most violent weeks since the protest movement began in June, prompting China's leader, Xi Jinping, to comment on the unrest for the first time, saying: "The continued radical violent criminal actions in Hong Kong have gravely trampled on rule of law and social order, seriously damaging the prosperity and stability of Hong Kong."

And he added the Chinese government strongly supports the Hong Kong police in enforcing the law.

But anger against the police has been growing, with many accusing them of using excessive force against protesters.

Universities have become the new flash-point, with intense confrontations between protesters and riot police, who fired tear gas, rubber bullets, and water cannon, and protesters retaliating with stones and crudely made gasoline bombs.

At the Polytechnic University, the campus has been turned into a fortress.

We have been preparing a lot of offensive and defensive weapons.

As you see, once you enter the university campus, a lot of people wear helmets and masks.

We are also making Molotov cocktails to protect ourselves and stopping the police from entering the university.

The university is a hive of activity, even though classes have been canceled until the end of the year.

Operations on the campus are well-organized, with different groups assigned tasks.

The kitchens feed anyone who wants a hot meal.

Among them are students, alumni, and those who want to help the mostly young protesters.

Frank Wong is one of them, despite being on the government's payroll.

As a search and rescue worker, he often works alongside the police and says he is concerned about the protesters safety.

The police force ordinance tells you that batons should never be used on the head.

That can cause death.

But that's what they do.

So the question is, do the police want to apprehend the protesters or kill them?

Along with defending their campus, the protesters are keeping watch over a tunnel right next to their university.

This is the Cross Harbour Tunnel.

It connects Hong Kong's financial center to the rest of the city.

It's normally very busy with heavy traffic, but the protesters have shut it down.

And by doing this, they have not only taken over a major transport route, but they are also sending a message to the government of how much they can disrupt the city.

It's part of a new strategy to create as much disruption as possible during the weekdays.

Small groups of protesters barricade roads and highways at peak hours to create commuter chaos.

If they can't go to work, then maybe it will have some pressure for the enterprise to -- so that they can give more pressure to the government.

The action has proved effective.

Schools were closed for the week, while many shops, business, and commercial outlets near protest sites are periodically shut, and public transport and trains canceled.

It's paralyzed the city and seems to have done the same to the government.

Despite the escalation with each week of protests, the city's leadership has yet to find a way to defuse the crisis.

For the "PBS NewsHour," this is Divya Gopalan in Hong Kong.