French authorities said yesterday they were calling in the army's health services to meet a surge in demand for vaccinations against swine flu, which has killed 30 people in the country.

Mass vaccination centres opened on November 12 but "since last week, the number of people seeking to be vaccinated against the A(H1N1) virus has been sharply increasing," the health and interior ministries said in a statement.

"The army's health services will be called as back-up," it said.

Medical students and in-house company doctors will also help meet high demand for the vaccination, the statement added.

The ministries said local authorities had been told to extend opening hours and increase capacity to cope with the surge in demand.

Police officials in Paris said yesterday they would double capacity in each of the French capital's 12 vaccination centres by "the middle of next week".

The number of people receiving the jab each day has risen from an average of 1,000 at the start of the campaign to around 4,000 last week, Paris police said in a statement.

In Lyon, France's second largest city, the main vaccination centre ran out of doses just one hour after opening yesterday morning.

"Usually we would close at 1 p.m., but we were overrun by 10.15 a.m.," said Lieutenant Colonel Daniel Quiessu, an official with the Lyon Fire Brigade, which is responsible for organising and managing the crowds outside the centres.

Quiessu said people were lining up outside the Ficelle gymnasium at 8 a.m., 90 minutes before it was due to open.