Sensex plunged over 1,000 points while Nifty opened below 25,550 weighed down by weak global cues from Iran-Israel conflict and FII selling. The fall also came after SEBI's new F&O rules, which experts said can strengthen market resilience but also introduce challenges. Crude oil prices traded higher with Brent crude futures rising to 0.87% to $74.54/barrel amid Middle East tensions.