China's Olympic Games run-up stuttered again when terrorists killed 16 policemen in the nation's far north-west, while pollution returned to fill athletes' lungs in Beijing.
The attack in the Muslim-populated Xinjiang region yesterday raised the security temperature ahead of the Olympics, which begin on Friday, as authorities repeatedly warned militants there were planning to sabotage the Games.
It follows deadly bomb blasts in the south-western city of Kunming last month and in Shanghai in May which killed five people and for which a Muslim militant group with ties to Xinjiang claimed responsibility.
Chinese Games organisers said they were checking for any link between the attack and the Olympic Games, but immediately sought to reassure the world about security arrangements.
Beijing Olympic organising committee spokesman Sun Weide said, ''We have strengthened security work in all Olympic venues and in the Olympic village. We are well-prepared in security for the upcoming Games.''
According to the official version of the attack published in the state-run media, two assailants in Xinjiang's Silk Road city of Kashgar killed 16 policemen and injured another 16.
The pair drove a truck at the police officers jogging near their barracks, Xinhua news agency said.
After the truck hit a roadside pole, the two got off and threw home-made explosives at the barracks, then moved in to hack at police officers with knives, Xinhua reported. It said both attackers were arrested.
Kashgar is 4000km from Beijing, close to the Tajikistan border.
Xinhua did not identify who the terrorists may be affiliated to, but China has said previously that Muslim groups seeking independence for Xinjiang and the creation of ''East Turkestan'' were a security threat.
Xinjiang, a vast area that borders Central Asia, has about 8.3 million ethnic Muslim Uighurs, and many are unhappy with what they say has been decades of repressive Communist Chinese rule. The East Turkestan Islamic Movement, which reportedly operates inside Xinjiang and in neighbouring Afghanistan, is listed by China, the United States and the United Nations as a terrorist group.
But exiled Uighur dissidents and some human rights groups say China's claims that the East Turkestan Islamic Movement is a major threat are exaggerated. A group calling itself the Turkestan Islamic Party claimed credit last month for the deadly bus blasts in Shanghai and Kunming. Some experts believe the Turkestan Islamic Party is part of the East Turkestan Islamic Movement.
After raising the alarm about Olympic terrorist attacks, China denied the Turkestan Islamic Party carried out those attacks, but said nothing more as to who may be responsible.
Another problem for China in the Games run-up has been Beijing's pollution, which International Olympic Committee president Jacques Rogge has said could lead to some endurance events being postponed.
A familiar heavy smog permeated the city yesterday. One million of the city's 3.3 million cars were taken off the roads from July 20, and more than 100 heavily polluting factories and building sites were closed down.
Chinese authorities have said they could take further measures if air quality remained poor, and officials said those emergency plans might kick in soon. AFP