My father in law did a tour on Siachen Glacier. Whose territory is whose is up for debate. When India and Pakistan partitioned themselves in 1947 India was supposed to get Kashmir. Pakistan didn't like that and immediately invaded India. The "Line of Control" in Kashmir reflects the cease fire line at the end of that first war which leaves . India is on one end of the Siachen, Pakistan is on the other end. I would argue that Pakistan has no business at all holding territory that is traditionally Buddhist, as all of eastern Kashmir is Buddhist. But Pakistan had crossed that cease fire line many times and attempted to grab additional mountains and passes. Most recent was a war in about 2000 in the Kargil district in Kashmir. Up to 5,000 KIA between the two sides.
GunLvr