Mumbai, Aug 31 - A key index of the Indian equities markets shut shop Monday 1.61 percent lower than its last close, ending a seven-day rally as investors booked profits and Chinese markets fell sharply.

The 30-scrip sensitive index (Sensex) of the Bombay Stock Exchange (BSE), which opened at 15,812.15 points, ended at 15,666.64 points, down 255.7 points or 1.61 percent.

The broader-based Nifty of the National Stock Exchange (NSE) closed lower at 4,662.1 points, down 1.48 percent.

Broader market indices, however, managed to close in the green, with the BSE midcap index closing 0.33 percent higher and the BSE smallcap index ending 0.51 percent up.

The market breadth was positive, with 1,648 stocks advancing, 1,154 declining and 78 remaining unchanged.

Of the 30 stocks on the Sensex, M&M led the rally, with a 4.15 percent increase to Rs.860.05 followed by DLF, up 2.67 percent at Rs.424.20; NTPC, up 1.19 percent at Rs.212.65, and Maruti Suzuki, up 1.03 percent at Rs.1,436.65.

The leading losers were Tata Steel, down 3.