Hong Kong has closed schools Thursday after the discovery of the city's first cluster of swine flu infections.  This comes as the World Health Organization holds an emergency meeting in Geneva to discuss the latest development on the spread of the H1N1 virus.

The cluster of infections was found in a secondary school, where at least 12 pupils fell ill with the H1N1 swine flu virus.

Hong Kong Chief Executive Donald Tsang cut short his trip in mainland China and returned to the territory to take charge of the city's response to the outbreak.  On Thursday, Tsang ordered all nurseries, kindergartens, primary and special schools to close for 14 days, in an attempt to stop the spread of the virus.

"The student committee has just confirmed the first cluster of local cases of human swine flu?We are unable to identify to identify the source of infection," he said.  "In accordance with our contingency plans, we will take the following key measures:  all primary schools, kindergartens, child care centers and special schools will close for 14 days from tomorrow [Friday]."

At least 1,600 schools and 500,000 students will be affected.

Tsang says Hong Kong is changing its flu pandemic response from containment to mitigation. 

The hospital authority says it will open eight designated clinics for patients with flu-like symptoms, starting Saturday.  There have been some 50 confirmed cases of swine flu in Hong Kong.

Hong Kong health authorities have warned that a local outbreak was inevitable because of the increasing number of infected people who have arrived in the territory in recent weeks.  Until this week, all of the flu cases in Hong Kong contracted the virus abroad - most in North America.

Clusters of infections worry Hong Kong authorities because this is how Severe Acute Respiratory Syndrome spread in the city, in 2003, killing nearly 300 people.

Elsewhere in Asia, swine flu fears prompted Philippine officials to delay the start of the school year from June First to June 15. 

Swine flu has spread to more than 70 countries, with more than 27,000 confirmed cases, worldwide.  The World Health Organization meets Thursday in Geneva to discuss recent developments and whether it should raise its highest pandemic alert.