Hong Kong - A team of scientists in Hong Kong said on Sunday they had identified a new virus believed to be behind the outbreak of a mysterious respiratory illness as the global death toll climbed to 12.

Canadian health officials said a third person in Canada had died after contracting the mysterious respiratory virus called Severe Acute Respiratory Syndrome (SARS), which has infected hundreds of others around the world.

Ontario's chief medical officer, Dr Colin D'Cuna, said the victim died on Friday, adding the province had eight probable and two suspected cases of the disease.

Elsewhere in Canada, two other possible SARS cases have been detected, one in British Columbia in the far west and the other in Alberta. The Alberta case involved a woman who recently returned from Hong Kong.

Hong Kong has been at the centre of the global outbreak since an American businessman succumbed to the disease here on March 13 after visiting China and Vietnam.

SARS has killed at least seven people in Hong Kong and infected another 222. Twelve people have died and 386 suspected SARS cases have been reported in 13 different countries, according to WHO figures.

News of the latest death came as University of Hong Kong scientists said they had cultured the virus that causes SARS, a deadly pneumonia-like illness.

The team isolated the virus from the lung tissue of a patient who developed SARS after contact with a doctor from southern China's Guangdong Province and later died.

The 64-year-old Chinese doctor is believed to be at the origin of the epidemic here.

The doctor, who died as a result of the disease, is believed to have infected at least seven other travellers who shared a hotel in Hong Kong's Kowloon district between February 15 and 27 and later went home to Canada and Singapore, sparking off a chain of infection.

Chief virologist at Hong Kong university, Malik Pieris, called the new virus "tricky" and stressed it was important to conduct more study before forming any conclusions.

The Geneva-based World Health Organization (WHO) said that with the virus now isolated, scientists could focus on characterising the agent, determine its relationship with known viruses and establish a definitive identity.

The results of the team's research will be shared among 11 leading laboratories in a global network set up by the WHO.

Klaus Stoehr, a WHO virologist who is coordinating the network, said the success achieved through mutual cooperation of scientists around the globe gave hope that SARS could be contained.

"Scientists, who are by default academic competitors, are now working virtually shoulder to shoulder. In less than a week, they have produced results which, in other circumstances, would likely have taken months or more. This rapid advance is fuelling the hope that SARS can and will be contained."

Tourism in countries hit by the virus has suffered in the wake of the outbreak despite the WHO reiterating on Friday that the global outbreak did not warrant any travel restrictions.

Despite the WHO assurance, the United States on Saturday stepped up its warning for US citizens against travel to Vietnam and said it would allow some diplomats and their families to leave due to fears about the spread of SARS.

At least 63 people in Vietnam, including the 10-year-old son of a US diplomat, are believed to have contracted the infection.

Hong Kong's tourism industry has been hit especially hard by the outbreak, and the decision of France and Italy to withdraw from an international rugby tournament here on Friday citing health worries dealt another blow to the territory's reputation as a dream holiday destination. - Sapa-AFP