SHANGHAI (REUTERS) - Three knife-wielding attackers have killed five people and injured another five in China's far western region of Xinjiang before police killed the "thugs", a regional government said, in the latest bout of violence on China's border with Central Asia.

The attack took place on Tuesday evening (Feb 14) in Pishan county in the restive southern part of Xinjiang, the government of Hotan prefecture said in a short statement on its website early on Wednesday.

"At present, social order is normal at the site, society is stable, and investigation work is under way," it said, without giving further details about the attackers or their motive.

Hundreds of people have been killed in recent years in resource-rich Xinjiang, on the borders of central Asia, Pakistan, Afghanistan and India, in violence between members of the ethnic Uighur minority and majority Han Chinese.

The government has blamed much of the unrest on separatist Islamist militants, although rights groups and exiles say anger at Chinese controls on the religion and culture of Muslim Uighurs is more to blame for the violence.

China denies any repression in Xinjiang.

Pishan, known as Guma in Uighur, has been the site of several security incidents in recent years. In 2011, police killed seven people they described as kidnappers who were members of a terror group.

Mr Dilxat Raxit, spokesman for the World Uyghur Congress exile group, said the latest incident of what he described as Chinese repression meant there was no way for people to show peaceful dissent. "Any provocation could lead to a clash," he said in an e-mailed statement.

There has been an uptick in violence in Xinjiang in recent weeks after a period of relative calm. In December, five people were killed when attackers drove a vehicle into a government building and police shot dead what authorities described as three terror suspects last month.

Hotan, a one-time Silk Road outpost, is considered part of the Uighur heartland, and has been at the frontline of what China terms its war on terror.

Earlier this month, the government said seven people, including six senior public security officials from Hotan and nearby Karakax county, were being investigated on suspicion of graft. All were Uighurs, judging by their names.