BEIJING--China executed two Muslim men in its far northwest on Thursday for a "terrorist" attack that was aimed at sabotaging last year's Olympics and left 17 policemen dead, state media reported.

The two members of China's Muslim Uighur minority group were put to death in the famed old Silk Road city of Kashgar, where the attack took place, Xinhua news agency reported.

The August 4 incident was the most serious in a wave of unrest in China's remote Xinjiang region ahead of, and during the Beijing Olympics, leaving dozens of people dead.

China blamed the violence on separatist militants from Xinjiang who wanted to use the global spotlight of the Olympics to raise awareness for their independence cause.

Xinjiang, a vast area that borders Afghanistan and Pakistan, has about 8.3 million Turkic-speaking Uighurs, many of whom say they have for decades suffered Chinese political and religious persecution.

The men executed -- Abdurahman Azat, 34, and Kurbanjan Hemit, 29 -- were sentenced to death in December after being convicted of carrying out the attack with the intention of trying to "sabotage" the Olympics, Xinhua reported.

Xinhua did not say how they were executed but in China the method is typically a bullet to the back of the head or lethal injection.

It said court officials made the execution announcement in front of 4,000 people at a stadium in Kashgar.

Chinese officials previously said the two were carrying documents advocating "holy war" that linked them to the East Turkestan Islamic Movement, listed by China and the United Nations as a terrorist organisation.

Two short-lived East Turkestan republics emerged in Xinjiang in the 1930s and 1940s, at a time when central government control in China was weakened by civil war and Japanese invasion.

On August 4 last year the pair drove a truck at a group of 70 police officers and then attacked them with explosives, machetes and knives, before being overpowered and arrested at the scene.

In a well-planned attack, the men were dressed as police, according to foreign eyewitnesses AFP spoke with in Xinjiang at the time.

Analysts said the violence across Xinjiang in August was the worst there for years and was partly triggered by Uighur separatists wanting to raise publicity ahead of the Olympics.

However, Xinjiang is thousands of kilometres from Beijing and no terrorist attacks directly threatened the Games or the Chinese capital.

This year marks 60 years since China's People's Liberation Army entered Xinjiang and implemented what it called a "peaceful liberation" of the region, but advocates of independence for the area view the move as an invasion.

While the Chinese government is looking to celebrate the anniversary, it has warned separatists are planning more attacks.

"The (security) situation will be more severe, the task more arduous and the struggle more fierce in the region this year," Nur Bekri, chairman of the Xinjiang regional government, said last month.

"It's a time of celebration for Xinjiang people but hostile forces will not give up such an opportunity to destroy it."

The US State Department in February said repression of Uighurs in Xinjiang worsened last year.

"The government tightly controlled the practice of Islam, and official repression of Uighur Muslims in the (region) increased," it said in a human rights report for 2008.

China arrested almost 1,300 people for terrorism, religious extremism or other state security charges in the region last year, Chinese state press reported recently.

China's foreign ministry declined to comment specifically on Thursday's executions, other than to defend the legal system.

"I can guarantee you that the local authorities always handle these kind of cases according to the law," ministry spokeswoman Jiang Yu said.