One Kevyt Konekivaan (KK) series rifle used by Itoo and two AK series rifles were recovered from the encounter scene.
Militants opened fire on an Army camp in Kupwara district of Jammu and Kashmir, injuring a jawan, police said today.
Two soldiers were killed and all the three militants were killed in a fierce encounter that lasted over 12 hours in south Kashmir district of Shopian.
The three militants, who are yet to be identified, were holed up in a house in Awneera village.
Itoo, often called a "vintage militant" as he joined Hizbul Mujahideen in 1996, had surrendered in 2007 and later released on parole in 2014.
He said as the forces were conducting the search operation, the militants fired upon them, resulting in injuries to two police personnel. Two injured soldiers later succumbed to critical injuries.
The police said there was information about presence of the militants in the area and the cordon was laid.
Over a dozen youth were injured in clashes with security forces as they pelted stones during the operation in Awneera village. The wounded policemen have been shifted to Srinagar for the treatment. However, many were injured during the protests which turned in to clashes as government forces resorted to tear gas shelling and pellet firing.
The slain Armymen have been identified as Tamil Nadu's Ilayaraja P, and Gawai Sumedh Waman from Maharashtra.