"It is totally unacceptable for people to damage our emergency vehicles, particularly when our staff are helping someone who needs urgent medical help," said Richard Clayton, East Midlands Ambulance Service Delivery Manager.

The incident took place during the morning of Sunday, in Blackthorn, Northampton.

Our crew were returning to their vehicle after responding to a 999 call and noticed a group of young people around it. As they drew near, the group ran off.

An implement had been used in an attempt to open the two front door windows, causing damage in the process.

Although there will be costs for body work repairs, the vehicle is still road worthy but this might not have been the case if the crew had not interrupted the actions of the group.

"It is beyond belief that someone would damage and possibly try to steal something from an emergency vehicle, let alone when the crew are trying to help a patient in need.

"The people that commit this kind of act against our service should be ashamed of their actions," added Mr Clayton.

"Our message is clear – this type of behaviour is not acceptable and we will take action. We will report such incidents to the Police, who we know take these crimes very seriously."

Nick Arnold, EMAS security management specialist, said: "When I was appointed last year, I made it my mission to reduce the threat of crime towards our staff and property.

"There are many ways of doing this but one of the best is to make the perpetrators face up to legal consequences.

"We will not tolerate violent, threatening behaviour or damage to our property and anyone who behaves in this way will be reported to the Police."