KASHGAR, China - The Associated Press

Police tightened security checks on roads and public buses in China's far western Xinjiang region yesterday, a day after a deadly attack on police heightened security jitters ahead of the Beijing Olympics.
The official Xinhua News Agency reported that authorities reinforced the police presence on roads leading into Kashgar and ordered a full security alert in public places, including government office buildings, schools and hospitals. Police boarded vehicles at checkpoints to search passengers' bags, Xinhua said.
In Xinjiang's capital of Urumqi, police used handheld devices to check residents' security cards in routine street patrols. Fully armed officers have been patrolling public bus routes since early July, Xinhua said.
Sixteen officers were killed and another 16 injured Monday in an audacious attack in which two assailants rammed a dump truck and hurled explosives at a group of policemen in Kashgar.
The attack in a city near the Afghanistan-Pakistan border brought an immediate response from China's Olympic organizers, who pronounced security precautions ready to ensure safety in Beijing and other Olympic venues when the games open Friday.
China has made safety a major priority for the Olympics, mobilizing hundreds of thousands of police, military and local residents as part of a huge security net over the capital. But the Xinjiang attack underscored that with so much security focused on Beijing areas far from the capital make tempting targets.
The timing so close to opening day heightened the attack's shock value.
"Security for the Olympic Games is of paramount importance. The more we give, the safer and more secure the residents will feel," Xinhua quoted Han Shubin, the deputy director of an Urumqi police division, as saying.
�Suspected terrorist attack':
The two attackers arrested on the scene were Uighurs, a mainly Muslim ethnic minority group, some of whom have waged a sporadically violent rebellion against Chinese rule.
Authorities have been calling the incident a suspected terrorist attack. Last month, an extremist Uighur group believed to be based across the mountainous border in Pakistan's tribal frontier threatened in a videotape to target the Olympics.
State broadcaster China Central Television said in its noon broadcast yesterday that the two men, aged 28 and 33, had premeditated the attack, stealing the dump truck and ramming it into some 70 border patrol paramilitary police as they passed a hotel during a morning jog. They then hurled the explosives and attacked the policemen with knives.
One of the attackers lost a hand when the homemade explosives blew up. Afterward, police recovered additional explosives, a gun, and "propaganda materials about a holy war," state media said.
Yesterday, the streets in northwestern Kashgar appeared quiet, though four soldiers in uniform and helmets were seen marching up the sidewalk on patrol, carrying short black clubs.
The assault took place on a tree-lined thoroughfare in front of the small Yiquan Hotel, housed in an older three-story building covered in dusty white, yellow and maroon tile.
The hotel was closed yesterday, with a large plastic tarp covering the entrance. Just to the right of the hotel, a group of four trees appeared to have been recently uprooted.
Underscoring tensions in the region, Chinese authorities clashed late Monday with two Japanese journalists who rushed to Kashgar to report on the attack, then later apologized to the newsmen after Tokyo said it would lodge a formal complaint, Xinhua and Japanese officials said.
The clash occurred when the journalists tried to film a restricted area, Xinhua said. Japan's Chief Cabinet Secretary Nobutaka Machimura told reporters in Tokyo that the two had been detained and roughed up adding: "We plan to lodge a strong protest."
Monday's attack was all the more surprising because it follows years of intensive security measures in Xinjiang. A wave of violence in the 1990s mainly targeted police, officials and Uighurs seen as collaborators. Also in the 1990s, separatists also staged nearly simultaneous explosions on three public buses in the provincial capital of Urumqi.In response, the government stationed more paramilitary units in the region and shut unregistered mosques and religious schools seen as hotbeds of anti-government extremism.