A top Ulfa(I) leader, Janardan Gogoi alias Jit Asom, and three cadres surrendered in Nagaland ahead of Independence Day. The others—Dweepjyoti Saikia, Anthony Moran, and Paragjyoti Chetia—gave up arms before Assam Rifles in Mon district. Security has been tightened along the Assam-Arunachal-Nagaland border amid terror threat alerts.