A respected forum of political, business and emergency service leaders have warned that 94,000 Londoners could die in a swine flu pandemic.

Their worst-case senario says half the cities population - 3.25 million people would be infected by the virus, leaving offices and schools shut and football games called off.

Red alert

The capital was already on red alert today after the first confirmed case struck in Barnet - the government's chief medical adviser has said Britain will see "many, many more cases."

An emergency task force is poised to trigger a crisis plan aimed at keeping the city running even if the deadly virus takes hold.

The plans from London’s Resilience Forum include:

● Response plans "should be ready for instant implementation" for services including health, education, the military, police, transport and councils.

● London health authorities should consider preserving essential stockpiled medical supplies.

● National stockpiles of antivirals may be pre-distributed.

● A series of emergency groups meet to coordinate response to the crisis.

The World Health Organisation yesterday raised the official threat level to five, one short of a full pandemic.

North London 'worst hit'

The projections suggested the boroughs most severely affected would be Ealing, with 4,235 deaths, and Barnet, with 4,113 deaths.

Planners are working on the basis of up to 2,500 flu-related deaths in a typical borough.

The organisation’s crisis plan says:

"The influenza pandemic will result in a large number of deaths throughout London. This means planning for approximately 94,000 possible excess deaths.

The aim is to minimise the possible social and economic disruption to the population in the vent of an outbreak of a pandemic."

The LRF reports to the Government and is co-chaired by John Healey, Minister for Local Government, and Tony McNulty, Minister for London and the Olympics, with Boris Johnson, Mayor of London as Deputy Chair.