Construction of the Tseung Kwan O Line was approved on 18 August 1998 to serve new housing developments. Construction began on 24 April 1999 and the line officially opened in 2002, taking over the train tracks running through the Eastern Harbour Tunnel from the Kwun Tong Line, running from Po Lam to North Point. When the line was opened, the Kwun Tong Line was diverted to Tiu Keng Leng on the new line. Construction costs were partly covered by the Hong Kong Government and private developers which linked construction of the Tseung Kwan O Line to new real estate and commercial developments. Previously less developed areas were opened up for development with more transport options.