Kashmir and occupied strategic locations enabling it to bring NH1 within range of its artillery fire. The next stage consisted of India discovering the infiltration and mobilising forces to respond to it. The final stage involved major battles by Indian and Pakistani forces resulting in India recapturing most of the territories held by Pakistani forces and the subsequent withdrawal of Pakistani forces back across the LOC after international pressure. Occupation by Pakistan During February 1999, the Pakistan Army sent forces to occupy some posts on the Indian side of the LOC. Troops from the elite Special Services Group as well as four to seven battalions of the Northern Light Infantry (a paramilitary regiment not part of the regular Pakistani army at that time) covertly and overtly set up bases on 132 vantage points of the Indian-controlled region. According to some reports, these Pakistani forces were backed by Kashmiri guerrillas and Afghan mercenaries. According to General Ved Malik, the bulk of the infiltration occurred in April. Pakistani intrusions took place in the heights of the lower Mushkoh Valley, along the Marpo La ridgeline in Dras, in Kaksar near Kargil, in the Batalik sector east of the Indus River, on the heights above of the Chorbat La sector where the LOC turns North and in the Turtuk sector south of the Siachen area. India discovers infiltration and mobilises Initially, these incursions were not detected for a number of reasons: Indian patrols were not sent into some of the areas infiltrated by the Pakistani forces and heavy artillery fire by Pakistan in some areas provided cover for the infiltrators. But by the second week of May, the ambushing of an Indian patrol team led by Capt Saurabh Kalia, who acted 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 infiltration, the Indian troops in the area assumed that the infiltrators were jihadis and claimed that they would evict them within a few days. Subsequent discovery of infiltration elsewhere along the LOC, and the difference in tactics employed by the infiltrators, caused the Indian army to realise that the plan of attack was on a much bigger scale. The total area seized by the ingress is generally accepted to between . The Government of India responded with Operation Vijay, a mobilisation of 200,000 Indian