BEIJING: Two men rammed a dump truck yesterday into a group of jogging policemen and tossed explosives, killing 16 officers, state media said, in an attack in restive western China that added to already high tensions days before the Beijing Olympics.

The attack was among the deadliest and most brazen in years in Xinjiang province, site of a sporadically violent rebellion by local Muslims against Chinese rule. Though it happened on the far side of China, the attack came as security forces were on alert for protests or any disruptions during the Olympics, which open Friday.

In Beijing, about 20 people upset at having been evicted from their homes staged a brief demonstration near Tiananmen Square, the capital’s heavily guarded political center. Uniformed police quickly surrounded the group until members of a neighborhood committee came and pulled the protesters away, scuffling with some.

In the Xinjiang attack, the two men drove the truck into police belonging to the paramilitary border patrol as they passed a hotel during a regular 8 a.m. jog in the city of Kashgar, the official Xinhua News Agency reported.

After the truck hit an electrical pole, the pair jumped out, ignited homemade explosives and “also hacked the policemen with knives,” Xinhua said. An earlier Xinhua report said the explosives were tossed at a barracks, but later the agency revised the account, saying their quarters were 200 meters away. Other accounts also said the men used a truck bomb.

Fourteen died on the spot and two en route to a hospital, while at least 16 were wounded, Xinhua said.

Police arrested the two attackers, one of whom was injured in the leg, it said.

Residents said authorities responded temporarily with intense security, closing off streets. The Nationalities Hospital, down the street from the explosion, was sealed and people were ordered to stay inside, said a man answering phones at the duty office.

An officer in the district police department said an investigation was under way.

Kashgar, or Kashi in Chinese, is a tourist city that was once an oasis trading center on the Silk Road caravan routes and is 130 km from the border with Pakistan, Afghanistan and Kyrgyzstan. Its mountainous, remote environs have allegedly provided cover for terrorist training camps, one of which Chinese police raided early last year.

Chinese security forces have been on edge for months, citing a number of foiled plots by Muslim separatists and a series of bombings around China in the run-up to the Olympics. Last week, a senior military commander said Muslims fighting for an independent East Turkistan in Xinjiang posed the single greatest threat to the games.

A spokesman for Beijing’s Olympic organizing committee, Sun Weide, said: “We’ve made preparations for all possible threats. With the help of the international community, we are confident to host a safe and secure Olympic Games.”