BEIJING — Police shot and killed five members of an alleged radical Islamic separatist group in the far west of China as Beijing tightened security ahead of next month's Olympic Games, state media reported Wednesday.

Two members of the group were hospitalized following a police raid on a hideout in Urumqi, capital of the northwestern territory of Xinjiang, the Xinhua News Agency said. Eight others were arrested, it said.

Xinhua said the group, which included five women, brandished knives and swore to fight to the death after more than a dozen police officers surrounded their apartment.

"The suspects confessed they had all received training on the launching of a 'holy war,"' Xinhua said.

Xinhua said the group was dedicated to establishing an independent Muslim state in Xinjiang and slaughtering members of China's majority Han ethnic group who have streamed into the region, 1,500 miles west of Beijing, since it was occupied by communist troops in 1949.

The reports come amid a nationwide security crackdown ahead of the Beijing Olympics that has targeted militants and government critics in Xinjiang and the Himalayan region of Tibet, the scene of deadly anti-government rioting earlier this year.

Authorities have previously accused Xinjiang separatists of attempting to crash an airliner in March and planning to kidnap athletes and journalists during the games.

At a rally for Olympic organizers in Beijing on Wednesday, Chinese Vice President Xi Jinping called security the single most important task for organizers in the runup to the games.

"A safe Olympics is the biggest indicator of the success of the games," Xi, tasked with supervising overall Olympic preparations, said in a speech at the Great Hall of the People, the seat of China's legislature.

"A safe Olympics is also a key indicator of the positive reflection of our nation's image," he said, underscoring the massive national prestige communist leaders have invested in the Aug. 8-24 games.

China claims Tibetan forces allied with the exiled Dalai Lama and Xinjiang separatists are seeking to torpedo the games with violent plots, including the use of suicide bombers. No evidence has been provided to support the claims, while critics accuse Beijing of using terrorism accusations to silence even peaceful dissent and often portraying ordinary criminal acts or civil unrest as terrorist-inspired in a bid to win public support.

Like Tibetans, Xinjiang's indigenous Uighur ethnic group has a language and culture distinct from that of China's Han ethnic majority, and extremists among them have waged a low-intensity struggle against Chinese rule for decades. Many have been sentenced to long prison terms or death on separatism charges.

Xinhua said police had been hunting the Xinjiang gang since they attacked a beauty salon in May and were forced to fire on the group Wednesday when they charged out of the apartment after tear gas was fired into it.

Calls to the police spokesman's office in Urumqi rang unanswered Wednesday, and a security guard at the Chenguan Garden community where the raid reportedly occurred hung up the phone when asked about the incident.

Beijing typically blames attacks in the area on the East Turkestan Islamic Movement, a militant group that demands separation from China, and which Washington claims is linked with al-Qaida.

Despite China's claims that terrorism is the main threat to the games, security experts say there is only a faint likelihood of attacks because of strict social controls.