ClowningA teenager dressed as a "killer clown" and brandishing a hammer has been stabbed after attempting to scare a group of young people.Police in Berlin said a 14-year-old in the group responded by pulling out a knife and stabbing the clown, only to find that the person behind the mask was a 16-year-old acquaintance.The 14-year-old boy then gave first aid until the emergency services arrived.The teenager dressed as a clown was taken to hospital, while the other was released to his parents.The clown craze - people dressing up in order to intimidate others - is thought to have started in the US, apparently influenced by Stephen King's horror story, It.