Market benchmark Sensex plunged nearly 400 points in opening session on Wednesday tracking losses in index-heavyweights RIL, HDFC twins and ICICI Bank amid heavy foreign fund outflow and weak global cues.

After starting over 393.03 points lower, the 30-share index pared some losses to trade 201.94 points, or 0.50 per cent, down at 40,079.26.

Similarly, the NSE Nifty dropped 58.10 points, or 0.49 per cent, at 11,739.80.

Top losers in the Sensex pack included Sun Pharma, Bharti Airtel, Tata Steel, Reliance Industries and HDFC shedding up to 2 per cent.

On the other hand, HUL, Nestle India, PowerGrid and Asian Paints were trading with gains.

In the previous session, the Sensex settled 82.03 points, or 0.20 per cent, lower at 40,281.20, and the Nifty declined 31.50 points or 0.27 per cent to end at 11,797.90.

According to traders, besides weak cues from global markets amid rising concerns over coronavirus outbreak beyond China, heavy foreign fund outflow too weighed on market sentiment here.

On a net basis, foreign institutional investors (FPIs) sold equities worth Rs 2,315.07 crore, while domestic institutional investors bought shares worth Rs 1,565.28 crore on Wednesday, data available with stock exchanges showed.

Stock exchanges in Hong Kong, Seoul and Tokyo were trading with losses, while bourses in Shanghai turned positive.

Equities on Wall Street plunged in overnight trade after American health authorities said they ultimately expect the novel coronavirus to spread in the United States and are urging local governments, businesses, and schools to develop plans like cancelling mass gatherings or switching to teleworking.

Brent crude oil futures rose 0.50 per cent to USD 54.53 per barrel.

The rupee appreciated 6 paise to 71.78 against the US dollar in morning session.