Yobs attacked a Kent Air Ambulance crew after they were called to help a scalded baby in Sevenoaks.

As a result the baby ended up being taken to hospital in a land ambulance and the helicopter - one of two flown by the air ambulance charity - was grounded for more than 12 hours until it could be inspected.

The attack happened soon after the chopper had put down on the Vine cricket ground off London Road, at about 4.30pm yesterday.

A passerby called police to report a disturbance.

But when officers arrived on the scene they were told two young men had been seen hanging off the tail fin of the helicopter and swinging on the pilot's door.

When the pilot asked them to stop it is alleged they became verbally aggressive and one of the men grabbed the pilot around the throat.

John Tickner, chief executive of Kent Air Ambulance said: "I find it incredible that anybody would want to attack a charity Air Ambulance and its crew, whose sole purpose is to help seriously injured people in their time of need.

"It is completely unacceptable that any of our staff are subjected to an assault and we will always fully support the police in any further action."

PC John Boyden said: "It is difficult to understand this sort of mindless behaviour. Why anyone would want to damage and abuse a service that provides a lifeline to people of Kent is beyond comprehension.

"It has been suggested that alcohol played a part in this incident but that is no excuse and the Sevenoaks neighbourhood policing team will be increasing patrols in the area and dealing with any such drink-related nuisance and anti-social behaviour robustly."

The helicopter was taken back to the air ambulance's headquarters in Marden and passed fit to fly at 11am today.

• A 19-year-oldhas been arrested onon suspicion of criminal damage and public order offences; and a 17-year-old on suspicion of common assault and public order offences. They have both been granted bail while inquiries continue.