Five people have died of swine flu in the last 24 hours in Mexico City, bringing the total of those killed to 15 in the capital, Mexico City's mayor, Marcelo Ebrard, told media on Sunday.

Ebrard said that 73 people were hospitalized with symptoms consistent with swine flu in the capital. Authorities have separately said that more than 1,300 have been hospitalized with such symptoms nationwide.

With these deaths, the number who have died of swine flue rose to 25 in the nation as a whole, where seven of the nation's 32 states are suffering the outbreak. Authorities are studying samples from a further 62 who have died suffering symptoms appearing to be swine flu.

But the Mexico government has not officially rechanged the death number.

Ebrard also ordered closure of two top courts in the capital, the Federal District Supreme Court and the Arbitrage and Conciliation Court, for an indeterminate length of time, in a bid to check any possible spread. He also closed the largest city parks Chapultepec Zoo and San Juan de Aragon Woods.

Ebrard also ordered that a million facemasks be distributed free on the city's public transport system, describing the city as experiencing "a critical moment."

The city government's first goal will be to "do all that is humanly possible to protect the population and brake the virus' spread."

The second most important thing is for those suffering symptoms to visit medical centers quickly, because those who are treated early have a better chance of controlling the virus, he said.

During the same conference, Armando Ahued, who heads the city's health department, said that three of the five dead were in city- run hospitals and the other two were in clinics run by the Mexican Social Security Agency.

The Supreme Court president, Edgar Elias, said separately that the courts would remain closed until at least May 6, but that local criminal courts would keep operating.