Thousands of Chinese troops poured into the restive city of Urumqi early yesterday in a massive show of force, as President Hu Jintao cut short a visit to Italy for the G8 summit to deal with the outbreak of ethnic violence.

Along one road ringing the capital of the western region of Xianjiang where 156 people died in riots on Sunday, The Times counted more than 30 paramilitary trucks, each followed by about two dozen men, many in black body armour, and most carrying riot shields, batons and fire arms.

The convoys included several white armoured personnel carriers accompanied by tear gas vans, all with paramilitaries standing ready to open fire. They were preceded by land cruisers, their sirens wailing as they moved almost at a walking pace through the town.

On the sides of the trucks were banners reading: "See the people as our father and mother."

In the centre of the city around People's Square, army helicopters circled overhead as hundreds more paramilitary troops marched in brigades of 20 to 30 chanting: "Defend the Motherland, defend the people."

A Han Chinese man surnamed Run said, as he watched the troops rolling by: "We support this. The Government has to take action to protect the people. But they should have got here sooner. It took them three days to do this. Why so long?"

Mr Hu's decision to return home came after another day of strife in Urumqi on Tuesday, as thousands of Han Chinese roamed the streets looking for vengeance after Sunday's riots, which left 156 dead and more than 800 injured.

He left Italy early yesterday "due to the situation in northwest China's Xinjiang Uighur Autonomous Region" Xinhua, China's state news agency, reported.

Mr Hu decided to curtail his trip "given the worsening of the disorder in Xinjiang", Tang Heng, the first political counsellor at the Chinese embassy in Rome, told Italy's ANSA news agency.

Although China is not a member of the Group of Eight, talks at the summit were to include emerging powers including China and India.

State Councillor Dai Bingguo would take part in the summit on Mr Hu's behalf, Xinhua reported.

Yesterday morning, the streets were quiet and cars began moving agin. But although the angry mobs had not returned, many Han Chinese were still carrying makeshift weapons in the city centre and outlying districts.

"I'm carrying this just for my own feeling of safety," said a man named Li as he walked near the city centre carrying a martial arts nanchuk — two batons held together by a chain.

One woman in her thirties was seen walking on the street carrying a large stick studded with nails, while others were carrying knives and steel poles.

Many shops and businesses remained closed and there were no buses or taxis running through the centre of town.

Chinese officials have already blamed the unrest on separatist groups abroad, which it says want to create an independent homeland of East Turkestan for the Uighurs. Rebiya Kadeer, the exiled Uighur businesswoman and activist blamed for the violence, denied having anything to do with it. She said: "These accusations are completely false."

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