Stretched ambulance crews had to call in more than £1million of emergency back-up because of a deluge of calls this winter.

South East Coast Ambulance Service (SECAmb) spent a total of £1,137,037 on hiring private ambulances in 2008.

The trust, which is responsible for about 4.5 million people from Kent to West Sussex and Surrey, did not spend a penny on back-up services in 2007.

But crews were so over-stretched when thousands of calls came flooding in last December, bosses were forced to fork out for help.

However, the cavalry did not come cheap, with each 12-hour shift costing about £72 an hour.

Private ambulance service provider Evolved Medical Services Ltd was commissioned to complete 1,306 shifts last year, most of them during what SECAmb called "severe winter pressures".

The figures were revealed after a Freedom of Information Act request by the KM Group's Dartford Messenger

The trust said it plans for expected peaks in demand, such as a five per cent increase in the number of emergency calls during winter months, but the eventual peak was far greater than it predicted.

In the first two weeks of December the trust said there was a 17 per cent increase in the number of patients being taken to hospital compared to the previous year.

During the same period, SECAmb received more than 4,000 additional 999 calls compared to the same period in 2007, an 15 per cent increase in demand.

The trust has been unable to say what factors may have led to the higher than usual rise, but said its increase was in line with others. The money required to fund the additional support came from the trust's budget.

A spokesman said: "In line with other ambulance trusts around the country, SECAmb has experienced severe winter pressures during the last few months. We have received an extremely high volume of 999 calls, way above of what was forecast.

"We took immediate action and put a number of measures in place to manage this high level of demand and safeguard patient care. This included increasing the number of front-line crews on the road dealing with emergency calls and redeploying clinically-trained staff to areas of increased 999 calls activity.

"We also commissioned the daily additional support of a private ambulance service provider to ensure we were able to meet demand and continue to provide a safe and responsive service for our patients."