Here is an Interview of Indian Army Officer taken by Defence Journal, Please read it yourself and find out what actually happened :-
DJ: You are the man said to have started the Siachen episode. Can you clarify this?
A: In 1978, when I was DMO we got information about a foreign expedition from the Pakistan side visiting the Siachen Glacier. The Line of Control, terminates at NJ 9842. The Glaciers are not demarcated. We sent a patrol next year and it was confirmed that Japanese expeditions had visited the Siachen Glacier. So routine patrolling started. Similarly routine protest notes used to be exchanged. **The problem precipitated on 21st August 1983 when a protest note from Northern Sector Commander of Pakistan was handed over to his counterpart in Kargil stating that Line of Control joins with the Karakoram Pass, also that all the area West of this extended line belongs to Pakistan. When Army Headquarters saw this and also got information that Pakistan troops had occupied Bila Fond Pass, they ordered Northern Command to prevent the occupation of the Glacier area by Pakistan during the mountaineering season in 1984. **
DJ: What happened?
A: What General Jahan Dad Khan has mentioned in his book “Pakistan Leadership Challenges” is absolutely true. You may like to quote him. It so happened that we chose our D day as 13 April 1984 and preempted Pakistan occupying the area. Your troops were in vigorous contact with us after April.
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*When the SSG company got across Bilafond Pass (in 1983), the helicopter pilot reported an Indian location one thousand yards ahead in the Siachen Area. After seeing our helicopter, the Indian troops, comprising Ladakh Scouts, left their location in a great hurry abandoning all their rations and tentage. The SSG company stayed in this area for ten days but was ordered to withdraw in the first week of September 1983 as it had started snowing and the company did not have equipment for survival in the winter season under thirty to forty feet of snow, which is the normal snow range.
The withdrawal of the SSG company was followed by many meetings in the GHQ to decide our plan of action for the summer of 1984 when the Indians were bound to come in greater numbers. Also taken into consideration was the fact that whoever succeeded in occupying the passes first would be able to hold them as it was impossible to dislodge them from these positions due to the terrain and the conditions. As Corps Commander, I gave the following assessment to the GHQ:
Next year (1984), India is most likely to pre-empt the occupation of the main passes of Baltoro Ridge with two-battalion strength for occupation and a third battalion as reserve. It would need another brigade to provide them with logistic support. Maximum helicopter force will have to be utilized for logistic support. Their air force will be available for air cover and also air drop of supplies/equipment.
We will need a brigade group with a battalion plus to occupy these passes and the rest of the force to provide relief and logistic support. We would also need maximum porter force to carry supplies and ammunition from Goma to the glacier position. All our helicopters force, both Aloutte and Puma, will have to be mobilized for recce and logistic cover. The PAF has to stand-by to provide air cover. I had also cautioned GHQ that this operation will be very costly in logistic support. Our Military Intelligence must be alerted to keep us informed of all enemy movements beyond Leh to forestall their occupation of the glacier area.
A meeting was held in December 1983, in the GHQ Operation Room under the chairmanship of President General Ziaul Haq. After listening to the 10 Corps Plan, the COAS thought that the operation on both sides would be on a limited scale, involving not more than a brigade on the Indian side and a battalion on Pakistan’s side. The COAS had obviously underestimated the quantum of force required by both sides. He had also under-estimated the logistic problem of this operation as presented to him by the logistic staff of the GHQ. In this meeting it was decided to incorporate the PAF in this operation and Maj Gen Pir Dad Khan (Commander of the Northern Areas) was given the task of pre-empting occupation of the passes, reaching there not before May 1984, as weather conditions before that period would not allow the use of helicopters and the PAF. This decision was to be approved by Defence Coordination Committee (DCC) attended by Chairman Joint Staffs Committee and all service chiefs. So preparatory work was started on the procurement of high altitude equipment and clothing, improvement of roads and tracks, recruitment of porters etc. All these preparations were to be completed by April 1984.
I handed over command of the 10 Corps to Lieutenant-General Zahid Ali Akbar Khan on 31st March 1984 after completing my tenure of four years. I gave him a detailed briefing about this operational plan and particularly stressed the importance of Intelligence keeping a watch on Indian moves beyond Leh. However, I learned later that when our troops approached the Baltoro Ridge passes during the third week of May 1984, the Indians were already in occupation of Gyong Pass in the south, strategically important because it could interfere with the enemy’s line of logistic support. As it was impossible to dislodge the Indians, we had no option but to occupy the next highest feature opposite them. This was a great setback for Pakistan, although all plans, including the timing of troop movement, had been laid down at the highest level. We had obviously failed to appreciate the timing of the Indian move and our intelligence agencies had failed to detect the movement of a brigade-size force in this area. It was learnt that the Indians had moved up their troops from Leh in the second half of April 1984.
After the occupation of these positions by both sides, opposite each other, the border became active. Both sides started inducting heavy weapons, including artillery guns, rocket launchers, and anti-aircraft missiles. Fire duels, patrol clashes, and engagement of helicopters through anti-aircraft guns became a daily affair. Both sides also brought up more troops to counter each other. Since then there has been no substantial change in the relative position of both sides. It was in the winter of 1984 that the Pakistani troops first experienced operating at that altitude. But the troops were provided high altitude equipment and there was no abnormal loss of life due to weather conditions. Pakistan was also able to induce French Lama helicopters to make up for our disadvantage vis-a-vis the Indians. *
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http://www.defencejournal.com/2000/june/interview.htm
Asif(K)