A Bristol grandad has spoken of his shock when a huge chunk of ice fell from the sky into his lap as he sat having dinner on his patio.

David Gammon, 76, says he heard a whistling sound before being hit on his left thigh by a grapefruit-sized block.

One suggestion is that the ice fell from more than 2,000ft from a plane because Mr Gammon's Stoke Bishop home lies underneath a flight path.

The retired banker was left with a big purple bruise on his leg, and said he felt he had a miraculous escape.

He said: "I consider myself extremely lucky to be alive. If the trajectory was just an inch to the side it would have hit my head and certainly killed me at that speed.

"I thought it must have been waste from an plane toilet, but it would have been a different colour if that was the case."

He described the moment when the ice hit: "The first I knew was a huge whistling sound. The next thing I know I can feel something fly an inch past my head, came over my shoulder and landed in my lap with an almighty thud.

"I instinctively leapt into the air in disbelief before the pain kicked in. I looked around and there were bits of crushed ice lying around where I'd been sitting – alongside the huge block which had hit me."

His wife Pamela, 67, put the ice in the freezer before replacing it with ice cubes to reduce the swelling.

Mr Gammon added: ''Ironically, I then sat there all night with ice on my lap to bring down the bruise."

The couple contacted the Civil Aviation Authority (CAA), which is investigating the incident.

Doctors have told David that there was no lasting damage done to his leg.

Richard Taylor, spokesman for the CAA, said: "It is quite rare for ice to fall from planes. There were only 35 instances in the whole of last year where ice has fallen from planes, although for it to actually hit someone is extremely uncommon.

"There have only been five instances where an individual has been struck since we started recording incidents more than 20 years ago.

"We will use the data which has been provided to work out which flight was passing overhead at the time and investigate the matter.

"It is possible there could be a leak in one of the seals on the plane, through which water has seeped and then frozen before falling.

"Ordinarily, the ice breaks up as it travels to earth, and falls as harmless water, but it appears as though it has stayed solid in this instance."