Oil and Natural Gas Corporation (ONGC) has plans to set up petrochemical complexes in Dahej and Mangalore.ONGC officials said that naphtha available from the MRPL refinery will be used for its proposed petrochemicals plant in Mangalore. ONGC has also obtained the necessary approvals for getting LNG at the Dahej terminal in addition to the Petronet supply of 2.5 million tonne per annum. The Dahej plant would be housed in a special economic zone (SEZ), which was being promoted by the corporation, officials said.