The equity benchmark indices posted their strongest weekly gains in years, driven by bargain hunting and optimism over a reversal in foreign portfolio investor (FPI) outflows.The Sensex rose 558 points, or 0.7 per cent, on Friday to close at 76,906, while the Nifty 50 gained 160 points to end at 23,350. Over the past five sessions, both indices advanced around 4.3 per cent - marking the Sensex's best weekly performance since July 22, 2022, and the Nifty 50's strongest rally since February 5, 2021.