The silver does not exist to cover these short positions, and it will take very little further buying to set off a crisis in this important market. In the case of gold, there have always been central banks with physical bullion available to ease market shortages, but so far as we are aware the strategic silver stockpiles of previous decades are exhausted. There is therefore no price at which these shorts can be closed.
Bank positions in both silver and gold seem to have been adversely affected by “events unknown” from the August BPR onwards. All attempts by the banking community to regain control of these important markets appear to have failed.
http://www.goldmoney.com/gold-research/alasdair-macleod/gold-futures-market-heading-for-crisis.html?gmrefcode=dollarc