URUMQI: Security forces armed with semi-automatic weapons and batons were deployed in China's restive Urumqi city as worshippers descended on mosques for the main Muslim day of prayer.

Muslim Uighurs heading to prayers had to pass rows of security forces, an AFP reporter witnessed, as Chinese authorities sought to prevent any repeat of the ethnic bloodshed that has blighted the city in recent weeks.

Many mosques had been closed last Friday for the first main prayer day following unrest that broke out in the capital of China's Xinjiang region on July 5 and left at least 192 people dead.

The main White Mosque in the city's Uighur district was overflowing with worshippers with many lining up prayer mats on the pavement outside, while around 200 paramilitary forces looked on close by.

The state-run Xinhua news agency said all 433 mosques in the city were open on Friday.

An AFP journalist at the White Mosque said afternoon prayers there ended and the worshippers left without any incident.

The July 5 unrest, the worst ethnic violence to hit China in decades, began with a peaceful protest by ethnic Uighurs but quickly turned violent. Uighur mobs attacked Han Chinese, the country's dominant ethnic group.

Chinese authorities say most of the dead were Han, and that more than 1,600 people were injured that day.

Thousands of Han Chinese retaliated in the following days, arming themselves with makeshift weapons and marching through parts of Urumqi vowing vengeance against the Uighurs. Sporadic unrest continued for days.

Violence broke out again on Monday, when police shot and killed two knife-wielding Uighurs and wounded another who authorities said had been calling for "jihad" at a mosque.

Uighurs, many of whom have complained of repression under China's 60-year rule in the huge region of mountains and deserts, have accused Chinese forces of opening fire on peaceful demonstrations.

Exiled Uighur leaders say the number of people killed is far higher than the official tally and that there were also attacks on Uighurs in other parts of Xinjiang.