Nifty has breached 16400 levels on 24 feb and closed below the level on daily chart. It was a critical support that has been breached. It will re-test 16800 -16840 levels on Monday for another selling for Target 16200/16000.
If it breaches 16000 levels further selling would come till 15500 support level.
Buy Nifty PE for 10 march weekly expiry if it does not cross 16800-840 levels.
Don't short above 16800 levels. Apply Stoploss accordingly.