A method of protection in response to a fault in a multi-terminal power transmission system, wherein the multi-terminal power transmission connects at least a first terminal, a second terminal and a third terminal, with at least a first transmission line connecting the first terminal and the second terminal, and a second transmission line connecting the third terminal and the first transmission line at a junction of the first and second transmission line, forming a section between each terminal and the junction on the first and second transmission lines, wherein each section (AJ, BJ, CJ) is one of an overhead line section and a cable, and the fault is located in one of the sections, wherein the method is performed with an Intelligent Electronic Device associated with one of the first, second and third terminals of the multi-terminal power transmission system, the method comprising: obtaining pre-fault and during-fault measurements of currents for each terminal of the multi-terminal power transmission system; calculating pre-fault and during-fault values of positive sequence current phasors from the pre-fault and during-fault measurements of currents for each terminal; the method characterized by the steps of: calculating at least two values (KA0, KA1, KB0, KB1, KC0, KC1) of a fault section index for each section, wherein each value of the fault section index for a section is calculated based on: an assumed value for fault location; a difference between the pre-fault and the during-fault values of the positive sequence current phasors for two terminals of the power transmission system, wherein the two terminals include the terminal that the section is connected at and one of the other terminals of the multi-terminal power transmission system; a length of the section; source impedances of the two terminals; and line parameters of the corresponding section; identifying the section having the fault based on a comparison of the values of the fault section index estimated for each section; and controlling a switching device according to the identification of the section having the fault, wherein auto-reclose is enabled based on the section being an overhead line section. obtaining pre-fault and during-fault measurements of currents for each terminal of the multi-terminal power transmission system; calculating pre-fault and during-fault values of positive sequence current phasors from the pre-fault and during-fault measurements of currents for each terminal; the method characterized by the steps of: calculating at least two values (KA0, KA1, KB0, KB1, KC0, KC1) of a fault section index for each section, wherein each value of the fault section index for a section is calculated based on: an assumed value for fault location; a difference between the pre-fault and the during-fault values of the positive sequence current phasors for two terminals of the power transmission system, wherein the two terminals include the terminal that the section is connected at and one of the other terminals of the multi-terminal power transmission system; a length of the section; source impedances of the two terminals; and line parameters of the corresponding section; an assumed value for fault location; a difference between the pre-fault and the during-fault values of the positive sequence current phasors for two terminals of the power transmission system, wherein the two terminals include the terminal that the section is connected at and one of the other terminals of the multi-terminal power transmission system; a length of the section; source impedances of the two terminals; and line parameters of the corresponding section; identifying the section having the fault based on a comparison of the values of the fault section index estimated for each section; and controlling a switching device according to the identification of the section having the fault, wherein auto-reclose is enabled based on the section being an overhead line section.