• Several shots fired during morning clashes
• Video shows one protester shot at close range
• 'There were three sounds, like pam, pam, pam' - resident
• Police say radical protesters set up barricades across city
• Anti-government protests now entering the sixth month

HONG KONG: Hong Kong police shot and critically wounded a protester and a man was set on fire on Monday as the territory spiralled into violence, prompting a warning from a Chinese editor that the mainland People's Liberation Army could step in at any time.

Protesters also threw petrol bombs at police on university campuses after a weekend of clashes at shopping malls across the territory, marking a dramatic escalation in more than five months of often violent pro-democracy unrest.

Hong Kong leader Carrie Lam said the "rioters" were destroying society and would not succeed in their demands with violence in the "special administrative region" (SAR) of China.

"If there's still any wishful thinking that by escalating violence, the Hong Kong SAR government will yield to pressure, to satisfy the so-called political demands, I'm making this statement clear and loud here: that will not happen," she said in one of her most defiant televised addresses.

Police fired tear gas in the narrow streets of the Central business district where some protesters, crouching behind umbrellas, blocked streets as office workers crowded the pavements and hurled anti-government abuse.

Some passersby took cover inside the Landmark mall, one of the oldest and most expensive, as volley after volley of tear gas rained down.

There have been almost daily protests in Hong Kong, sometimes with no notice, but it was rare for tear gas to be fired during working hours in Central, lined with bank headquarters and top-brand shops at the foot of Victoria Peak. Some offices closed early and workers headed home.

China has a garrison of up to 12,000 troops in Hong Kong who have kept to barracks throughout the unrest, but it has vowed to crush any attempts at independence, a demand for a very small minority of protesters.

The editor in chief of China's Global Times tabloid, published by the state-owned People's Daily, said Hong Kong police had nothing to be scared of.

"You have the backing of not only Hong Kong and Chinese people, but also Chinese soldiers and People's Liberation Army in Hong Kong," Hu Xijin wrote on his blog. "They can go into Hong Kong to provide support any time."

Police fired live rounds at close range at protesters in Sai Wan Ho on the eastern side of Hong Kong island and one 21-year-old protester was wounded. Police said the victim was in critical condition.

Anson Yip, 36, said protesters were building a road block when police ran to the scene.

"They didn't fight and the police ran and directly shot. There were three sounds, like 'pam, pam, pam'," Yip said.

Video footage showed polystyrene boxes and other debris littering a cross-section and blocking traffic. A protester wearing a white hoodie and mask walks towards a policeman, as if to challenge him. The officer draws his gun and points it at him at close range and grabs him round the neck.

As the officer holds the man with his left hand, he shoots another approaching masked protester at close range with his right hand. Three shots ring out and the man falls to the ground.

The fallen man is pinned to the ground by an officer holding a gun to his head. The man in white escapes.

A friend visited the wounded man in hospital.

"My friend didn’t actually attack the police or do anything," Rigan, 19, said. "They just shot him. My friend is optimistic, friendly and willing to help others."

The man fell just a couple of metres from a large makeshift memorial to a student who died from a fall in a car park last week, the blood staining the street next to candles, flowers, and anti-government posters.

"The live rounds fired by police are clear evidence of reckless use of force," Amnesty International Hong Kong said in a statement, demanding an investigation. "Another policeman was seen driving at high speed into a group of protesters on a motorbike. These are not policing measures – these are officers out of control with a mindset of retaliation."

Police said the motorcycling officer had been suspended.

Video images circulating online also showed a man dousing petrol on another and setting him on fire outside Ma On Shan Plaza in the New Territories. Engulfed in flames, the man was able to rip off his shirt and douse the blaze. Police said the man was in critical condition.

More than 60 people were wounded on Monday, Lam said in her address.

The unrest also spread to Causeway Bay on Hong Kong island and to Mong Kok, one of the most densely populated areas on earth, on the Kowloon peninsula, both often the sites of street clashes. Police used water cannon to break up protesters in Mong Kok.

Police said more than 120 places has been either vandalised or blocked on Monday. Some 266 people had been arrested since last Monday.

RED LINE

Protesters are angry about what they see as police brutality and meddling by Beijing in the freedoms guaranteed to the former British colony by the "one country, two systems" formula put in place when the territory returned to Chinese rule in 1997.

Some have called for independence, a red line for Communist Party leaders in Beijing. China denies interfering and has blamed Western countries for stirring up trouble.

The violence comes after student Chow Tsz-lok, 22, died in hospital last week following a fall as protesters were being dispersed by police.

Police fired tear gas at Chinese University, across the river from Ma On Shan, where students hurled petrol bombs and barricaded the campus like a fortress. There were at least four arrests.

"I feel a strong sense of helplessness," said one Chinese University student who gave his name as Chan. "Who wouldn’t want to attend class if they could? The government still isn’t listening to us."

He was guarding a back gate of the university on the old, rural Tai Po Road that snakes uphill from Sha Tin and often features in 1960s black and white Cantonese romance movies. The road was barricaded with fencing, wooden boards, bamboo, poles, bins and other debris.

The university said it would again suspend classes on Tuesday.

Protesters set fire to debris and threw petrol bombs at police at the Polytechnic University on the Kowloon side of Victoria Harbour after they briefly blocked the nearby entrance to the harbour tunnel. Petrol bombs were also thrown at Hong Kong University on the main island.

Hong Kong's stock market, which has been fairly resilient in recent weeks, closed down 2.6%, outpacing losses in other parts of the region.