A man's best friend: Jasper and Adam are reunited

It has been a social media campaign involving hundreds of thousands of people. One man's search for his lost dog captivated online users - on Twitter the hashtag #findjasper was used by people from all over the world.

It's a happy ending because Jasper the Border Collie has been found, three days after getting lost during a walk on Scafell Pike in the Lake District. Hannah McNulty met up with the very tired Jasper and his very happy owner.