Benchmark indices Sensex and Nifty declined by more than half a per cent at close on Monday due to selling in IT, power and metal shares triggered by a global equity meltdown on rate hike fears and FII outflows. Snapping its five-day gaining streak, the 30-share BSE Sensex settled lower by 334.98 points or 0.55 per cent at 60,506.90. During the session, the index fell over 500 points to touch its intra-day low of 60,345.61.