MECCA - Four pilgrims in Saudi Arabia for the annual hajj pilgrimage have died of swine flu, the health ministry said in a statement carried by the official SPA news agency on Saturday.

It said a Moroccan woman, a Sudanese man and an Indian man -- all aged 75 -- had died from A(H1N1), as had a 17-year-old girl from Nigeria. The ministry said the four had not followed "recommended procedures, especially vaccination against swine flu."

Health authorities in the kingdom have mobilized for the world's largest gathering since swine flu began spreading across the globe after it was first reported in April.

Hundreds of thousands of pilgrims from across the globe have already gathered in the country to perform the hajj in the holy Muslim cities of Mecca and Medina.

The peak day in the hajj is Thursday, November 26, when pilgrims gather at Mount Arafat, where the Prophet Mohammed gave his final sermon.

For the hajj, thermal cameras were installed at air and sea terminals in Jeddah where most pilgrims arrive, some 15,000 health workers are deployed, and hospitals have hundreds of extra beds available.

In Medina and Mecca, as well as in Jeddah, the government has taken measures to identify the virus in suspected cases.

The health ministry also has mobile units which can instantly send to a central monitoring centre the locations of infections, to monitor outbreaks.

On November 11, the Saudi authorities reported that 70 people had died in the country from the disease and said that more than 7,000 proven cases had been recorded.

On Friday, World Health Organization data showed that around 6,750 people had died from swine flu worldwide since the virus was first uncovered in Mexico and the United States in April