Initial infiltrations were noticed in Kargil in early May 1999. Because of the extreme winter weather in Kashmir, it was common practice for the Indian and Pakistan Army to abandon forward posts and reoccupy them in the spring. That particular spring, the Pakistan Army started reoccupying the forward posts well before the scheduled time. In a preliminary step in their bid to capture Kashmir, they reoccupied not only their own posts, but also 132 posts that belonged to India.[2]
By the second week of May, an ambush on an Indian army patrol acting on a tip-off by a local shepherd in the Batalik sector led to the exposure of the infiltration. Initially with little knowledge of the nature or extent of the encroachment, the Indian troops in the area initially claimed that they would evict them within a few days. However, reports of infiltration elsewhere along the LoC soon made it clear that the entire plan of attack was on a much bigger scale. India responded with Operation Vijay, a mobilisation of 200,000 Indian troops. However, because of the nature of the terrain, division and corps operations could not be mounted; the scale of most fighting was at the regimental or battalion level. In effect, two divisions of the Indian Army,[3] numbering 20,000, along with several thousand from the Paramilitary forces of India and the air force were deployed in the conflict zone.
the Indian Army moved into the region in full force. The intruders were found to be well entrenched and while artillery attacks had produced results in certain areas, more remote ones needed the help of the air force. To avoid the escalation, the Government of India (GoI) cleared only limited use of Air Power on May 25, more than three weeks after first reports, with the instructions that IAF fighter jets will remain within Indian territory to launch attack on intruder's position within Indian territory and IAF was not permitted to cross the Line of Control under any circumstance.
The lessons learned in this limited war influenced Indian Air Force to upgrade its combat fleet. It acquired and later started co-developing SukhoiSu-30MKI heavy fighters with Russia beginning in the early 2000s. Development of HAL Tejas was also accelerated. [citation needed]
