According to the New York Daily News, world-famous anonymous street artist Banksy thanked a 14-year-old kid, who had helped him pick up his paints, by giving him a signed painting which is expected to be worth around £20,000.

The man, who had introduced himself as Robin Banks, dropped his paints when he opened up his rucksack, which also contained a gas mask. “He got out a piece of paper and had colours marked on it of what he had been trying out and he dropped his colours,” said the teenager. Banksy then asked the boy if he knew who he was, when he said he didn’t he gave him the artwork, adding that it would probably be worth around $30,000 and told him “Have a good life, brother.’

The teenager described Banksy as a white man in his late 40s with “scruffy clothes” and an old, fluffy hat. “He had a little jacket that didn’t go over his arms and jeans with paint on. He looked really wacky and had blonde hair and blue eyes.” The boy said he plans to sell the artwork.