A knife fell from a residential building and landed beside a mum and her daughter in eastern China.br br The shocking video, filmed in Hefei city in Anhui province on July 20, shows a woman sitting in front of a shop watching her daughter playing.br br A 20-centimetre-long knife suddenly dropped down and landed upright into the ground, only a metre away from them.br br Fortunately, no one was injured. The case is being investigated.