DORSET'S ambulance service is having to rely on St John volunteers as the hot spell sends casualty call-outs soaring, service chiefs admitted today.

A huge increase in calls over the summer is being blamed for Dorset Ambulance NHS Trust asking St John Ambulance members to deal with non-urgent incidents, such as transporting patients to hospitals.

Ambulance chiefs said the service has received an average of 250 emergency and urgent doctors' calls per day during August - up 25 per cent on 2002.

Roger Ferre, the trust's director of operations, blamed the number of people collapsing in the unusually hot weather for the rise in workload.

He said the Dorset service received 296 emergency and urgent calls on August 10.

He said: "There has been a bigger strain on our resources over the last month or so through the hot weather which has caused St John Ambulance to do more and more of our routine daily business.

"We always prioritise jobs to ensure life-threatening incidents are attended by ambulance crews."

Union bosses said members were being put under increased strain through the rise in emergency calls.

Bill Cowlin, Unison branch representative for Dorset Ambulance NHS Trust, said: "We are having to cover more and more work this time of year and the bottom line is that we simply don't have the capacity or resources to do everything."

An elderly care worker, who asked not to be named, said: "St John Ambulance does a great job, but if someone calls for an ambulance they expect paramedics."

Peter Brown, chief commander of St John Ambulance, said: "We work with the ambulance trust providing first aid and transport assistance to the community. Our volunteers are fully trained and we are happy to help the trust whenever they need it."