The estimated death toll from swine flu in Mexico has risen to 152, officials have said, as fears of a pandemic grow.
"We're in the decisive moment of the crisis. The number (of deaths) will continue rising," said Mexico's health minister Jose Angel Cordova.
He claimed it was too early to identify the cause or geographical source of the virus, which is now thought to have infected close to 2,000 people in the country.
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However, Mr Cordova told reporters that a case in the southern state of Oaxaca was the first that had made them aware they were not dealing with a normal seasonal variation of flu.
Mexican authorities have shut schools across the country and are attempting to follow up families of swine flu victims in a bid to stop the spread of the virus.
In the country's popular tourist resorts, precautions are also being taken.
