Mumbai: The Bombay Stock Exchange benchmark Sensex declined by nearly 51 points in cautious opening trade on Tuesday as funds and retail investors locked in gains recorded in the previous session.

The 30-share Sensex, which had gained over 200 points in the previous session, fell by 50.72 points, or 0.31 percent, to 16,290.98 in opening trade on Tuesday.

In a similar fashion, the wide-based National Stock Exchange Nifty index shed 15.20, or 0.31 percent, to 4,883.60 points.

Brokers said profit-booking by funds and retail investors after handsome gains were recorded in the previous session mainly dampened the trading sentiment in the absence of any positive cues.

They said besides heavyweight stocks, small and mid-cap counters were also under some pressure.