The BSE benchmark Sensex plunged by over 400 points at midsession today on heavy selling by funds triggered by a steep fall in industrial growth amid weak global trend.

The 30-share barometer dropped by 402.22, or 2.37 per cent to 16,464.75 at 1200 hrs with all sectoral indices trading in the negative zone.

The broad-based National Stock Exchange index Nifty tumbled by 128.20, or 2.47 per cent to trade below 5,000 level at 4,931.25 at the same time.

Industrial growth falls to a meagre 3.3 per cent in July as against 9.9 per cent in the same month last year, which affected negatively the trading sentiments.