ED sources have told CNN-IBN that Hasan is probably the key man who is investing black money on behalf of top politicos, businessmen and bureaucrats.
The ED believes that in order to crack the exact source of these funds it needs to delve deep into the P-Note mechanism, but the Finance Ministry is not keen to pursue the matter, keeping in mind the fact that the markets are already treading on slippery ground.
Please explain the highlighted ones.
Look up bureaucrat in your dictionary
When there has been rain, the ground will become slippery and you might fall over, or slide on the wet mud - here it is a metaphor for uncertainty in the stock and money markets.