Sixteen Chinese policemen have been killed in an attack on a border post in the restive Muslim region of Xinjiang, state media say.
Two attackers reportedly drove up to the post in a rubbish truck and threw two grenades, before moving in to attack the policemen with knives.
The attack came four days before the opening ceremony of the Olympic Games.
Both attackers were captured during the raid near the city of Kashgar, Xinhua state news agency reported.
Kashgar, known as Kashi in Chinese, is some 2,500 miles (4,000km) from Beijing, near the border with Tajikistan.
Xinhua said the attack happened at about 0800 (0000 GMT), as the policemen were jogging outside the compound.
Although the episode happened a long way away from Beijing, the very fact that it happened, and the fact that it happened this week, will make the organisers of the Beijing Olympics nervous, says the BBC's James Reynolds in Xinjiang.
Fourteen policemen died at the scene of the attack and two on the way to hospital. Another 16 policemen were hurt.
One of the attackers was reported to have been injured in the leg.
Xinjiang, in the north-west of the country, is home to the Muslim Uighur people. Uighur separatists have waged a low-level campaign against Chinese rule for decades.
Human rights groups say Beijing is suppressing the rights of Uighurs.