Sensex, Nifty50 flat; Dr Reddy's down 4%

The S&P BSE Sensex started on a cautious note following muted trend seen in other Asian markets. The fall in the index was led by losses in Dr Reddy's Laboratories, HDFC, Bharti Airtel, and ICICI Bank. The Nifty50 slipped broke below its crucial psychological support level of 7,700, weighed down by losses in consumer durable, realty, power, and telecom stocks.