of over 1,500 km of roads and bridges, Paro Airport and Yongphulla Airport (upgraded in 2018, with scheduled fixed-wing civilian flights), heliports and other infrastructure. While these serve India's strategic defense needs, they are also an obvious economic benefit for the people of Bhutan. Army aviation The Royal Bhutan Army relies on Eastern Air Command of the Indian Air Force for air medical evacuation assistance. Indian Air Force helicopters evacuated RBA casualties to India for treatment during Operation All Clear in 2003. 2003 Operation: All Clear During the early '90s Indian separatist groups United Liberation Front of Asom (ULFA), National Democratic Front of Bodoland (NDFB) and Kamtapur Liberation Organization (KLO) had begun to clandestinely set up camps in Bhutan's dense southern jungles. These camps were used to train cadres, store equipment and launch attacks on targets in India. The Bhutanese government became aware of their presence in 1996, and from 1997 the issue was regularly discussed in the National Assembly. The Government of India began exerting diplomatic pressure on the Royal Government to remove the militant presence and offered to conduct joint military operations with Bhutan against the militants. The Royal Government, preferring a peaceful solution, declined the offer and instead initiated dialogue with the militant groups in 1998. By December 2003 negotiations had failed to produce any agreement and the Royal Government, unable to tolerate the groups' presence any longer, issued a 48-hour ultimatum on 13 December. On 15 December the RBA commenced military operations against the militant groups. Combat operations Under the leadership of His Majesty the 4th King, the RBA and RBG, with a total strength of 6,000, attacked an estimated 3,000 militants spread across 30 camps. By 27 December 2003 all 30 camps had been captured. Additionally, the RBA seized "more than 500 AK 47/56 assault rifles and 500 other assorted weapons including rocket launchers and mortars, along with more than 1,000,000 rounds of ammunition. An anti-aircraft gun was also found at the site of the GHQ of the ULFA." By 3 January 2004 all 30 camps (ULFA-14, NDFB-11, KLO-5) and an additional 35 observation posts were destroyed and the militants dislodged. A total of 485 ULFA, NDFB and KLO militants were killed or captured; those captured along with the seized weapons and ammunition were handed over to the Government of India. Captured non-combatants were handed over to Assamese civil authorities. The RBA suffered 11 soldiers