A composite photo shows two views of the Hong Kong skyline taken from the same viewpoint in Tsim Sha Tsui district of Kowloon, China; the top image taken at 6pm on 17 September 2007 when Hong Kong's 'Air Pollution Index' reached 'High to Very High'; the lower image taken at 6pm on 20 June 2007, when Hong Kong's 'Air Pollution Index' reading was 'Low'. A new study released on 17 September 2007 by Hong Kong think tank 'Civic Exchange' stated that drastic action needs to be taken to reduce air pollution in the city to attract and retain foreign investment, as well as to protect public health