In the Navy's biggest-ever event, ships from 50 countries have converged off the coast of Andhra Pradesh for inspection by President Pranab Mukherjee. India alone is parading 75 warships for the ceremonial inspection; 24 international warships have also sailed in. But the event, designed to display India's naval might and prowess, is surrounded by grave security concerns, partly because of the deadly terror attack last month at the Pathakot air force base in Punjab, where seven military personnel were killed.