The benchmark Sensex plunged nearly 300 points by midday on heavy selling by funds and retail investors on the back of weak overseas trend triggered by Bank of Japan's rate hike decision and further jump in crude oil prices.
The Bombay Stock Exchange's 30-share sensitive index dropped by 294.74 points at 10,563.76 at 1300 hours as foreign and domestic funds off-loaded part of their holdings on weakening global markets.
Similarly, the National Stock Exchange index Nifty fell by 79.45 points at 3089.85.
Marketmen said that BoJ's decision to end its zero-rate policy after nearly 6 years further weighed down on the market, which was already treading on a sluggish note on the back of fresh inflation fears triggered by record high crude oil prices.
Widespread selling pressure was being witnessed on the bourses while dragging all the 30 Sensex stocks and 50 Nifty shares deep into the red.