The "frontliners" - the most violent and daring protectors - have been at the barricades all summer.

In a siege, though, it is supply lines that count.

Hong Kong Polytechnic University has been turned into a fortress, occupied by protesters.

Image: Sky News went behind the scenes at the protesters' support network

Inside, that fortress is staffed by a volunteer logistics brigade.

All summer and into autumn, the Hong Kong protests have relied on a network of supporters - taxi drivers, medics, graphic designers. Unwilling to hurl a petrol bomb but all of them willing to lend a hand.


Here, though, they are running a campus, one designed for 20,000 people. And they're running it well.

There is no hierarchy nor assigned role.

People show up and find themselves a job. And out of that chaotic approach, an efficient, busy operation has emerged.

The food court is the hub of the university - this is Hong Kong after all. Tired protesters clad in black queue to pile their plates high with food.

Image: 3,000 meals are cooked every day

The kitchen is all go at lunchtime. There are different stations - one for separating eggs, another for chopping vegetables.

One protester wearing a mask instructs another on the best technique for peeling a courgette.

The dish-washing section declines an interview because they don't want to be identified.

Industrial-size woks hiss with oil. Most of these people are not protesters but fellow citizens who have come to lend a hand.

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One man (everyone I spoke to asked not to be named) is cooking chilli chicken. "I wanted to do something to help the protesters, to support them," he says. He adds they are cooking 3,000 meals a day.

Behind him are rows of freshly chopped ingredients and next to him is another, older man, who is retired, a former primary school teacher. "The Hong Kong government is doing something really wrong.

"So I saw the students, I come and help them."

He's been frying pork all morning but is done: "They don't want any more pork chop!"

Desperate plight of some Hong Kong residents

If an army marches on its stomach, this one will do just fine.

In another part of the university, there is a field hospital. It is stacked with medical supplies and strewn with beds to treat their wounded. Most of the injuries so far have been sustained in building roadblocks.

About 40 people work here, giving first aid. One of them, a young student from a different university, explains why.

Why are people protesting in Hong Kong?

"A lot of people still refuse to be in the frontline so they try to find a role. People drive their car to transport people back home. They try to support the students and youth in any sort of way they want. Because I think everyone in Hong Kong is enraged.

"People in the frontline can do their work. People in the back can support them. Just like us."

He shows me a home-made stretcher. "This one actually has wheels. It kind of moves," he says, rocking it.

Image: These people keep the protesters warm and fed

"A few months ago, we never thought we'd need to bring stretchers. We thought that the only wound we'd need to deal with are bruises or being affected by tear gas. But a few months later we see gun wounds, we see all sorts of stuff. And it's kind of crazy when we think about it."

More menial jobs are just as important.

I saw one middle-aged man scrubbing the toilets, then pushing a cleaning machine in the corridor. He studied at this university 19 years ago and has come to support the younger generation.

"This is the only thing I can do," he says. "Those who stand in frontline - it's not for me. I'm too old. So what I can do here, only do some cleaning, give them a good environment to stay, that's the only thing I can do."

He says he will stay as long as the protesters do.

But it works the other way too. The longer people like him lend a hand, the longer the protests will endure.