Visitors at Bristol Zoo got a bit of a surprise when this grumpy gorilla flipped his middle finger at a photographer trying to take his picture.

Bob Pitchford, 67, was on a visit to the city's zoo last week when he spotted the large ape chewing on some grass.

He took his camera out to take a photo but when the the mammal caught sight of Mr Pritchard he swiftly made the rude gesture.

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Rude: The gorilla was spotted unwittingly flipping his middle finger at the camera at Bristol Zoo last week

The photographer said: 'As I spotted him he was just playing with some grass. Gorillas have fantastic hearing so when I started clicking he must have heard me.

'He just turned around and it looked like he was flipping me the middle finger.'

Mr Pritchard didn't realise he had captured the hilarious shots until he got home and checked his photos.

'When I saw the pictures, I just thought "you little devil",' he added. 'He really does look a bit cheese off.

'I quite regularly photograph the animals at Bristol, but I've never seen anything like this.

'Gorillas are really good at expressing their feelings. I was just really lucky to capture this.'