The Indian Navy will kick-start a two-day mega defence exercise on Tuesday covering the country s 7516 km coastline and exclusive economic zone, officials said. Billed as India s largest coastal defence exercise, it will involve all the 13 coastal states and Union Territories along with other maritime stakeholders, they said. The second edition of the biennial pan-India coastal defence exercise Sea Vigil-21 will be conducted on January 12-13, the Navy said. It said the scale and conceptual expanse of the exercise are unprecedented in terms of the geographical extent and the number of stakeholders involved, units participating and objectives to be met.