The Indian equity benchmarks erased early gains with Sensex dropping nearly 600 points from day’s highest level and Nifty 50 index falling below its important psychological level of 17,300 on reports of spurt in geopolitical tensions between Russia and Ukraine. Russian news agency Sputnik reported that Ukraine violated ceasefire after Ukrainian Armed Forces fired mortar shells and grenades on self-proclaimed Luhansk People's Republic at 2:30 am GMT. Meanwhile, analysts warned for heightened volatility during the session owing to weekly expiry of index futures and option contracts.