Benchmark index Sensex dipped over 900 points to close at 76,631.65 on Thursday, while the Nifty crashed 0.93% to end at 23,775.10. The dip comes after fresh attacks by Israel on Lebanon raised concerns about the viability of the two-week ceasefire between Iran and the US. Sensex closed nearly 2,950 points higher on Wednesday after the ceasefire announcement.