Why IOs being transferred suddenly ?

Four Investigating Officers, who were looking after sensitive cases, have been suddenly transferred on administrative grounds. This has created ripples in ED. After IOs who were probing cases related to Robert Vadra, August VVIP Helicopters, Sandesra, now IO Dinesh Chauhan is the latest victim of sudden transfer. He has been shifted from Jullundhar to Srinagar. He was investigating cases related to Drugs in Punjab. Experts says that such actions show some "hidden" intention of the Investigating Agency. Who can spell out the reality ?