I was on the Underground travelling on the Northern line. A man of Arabic appearance got off the train and I noticed that he had left his bag behind. I grabbed the bag and ran after him, caught up with him at the top of the escalator and handed him back his bag.

He was extremely grateful to me and reached into his bag which appeared to contain large bundles of banknotes. He offered me a reward, but I refused.

"So he looked round, made sure nobody was looking and whispered to me: "I can never repay your kindness, but I will try to with a word of advice for you. Stay away from Aberdeen Steak Houses."

I was terrified. "Is there going to be an attack?" I whispered.