India showcased its military might and cultural heritage as it celebrated its 68th Republic Day on Thursday amid heavy security and terrorist threats. Abu Dhabi Crown Prince Sheikh Mohammed bin Zayed al-Nahyan was the chief guest at a military parade in New Delhi, the main attraction of national celebrations to commemorate the country's 1950 constitution. Nearly 50,000 police and paramilitary personnel were deployed across the city after intelligence warnings that terrorists could launch an air attack, by way of a drone or hijacking, or by disguising themselves as security personnel. In India's insurgency-hit north-east, militants triggered 11 low-intensity blasts, but there were no injuries or damage. Seven of these were at "abandoned places" in Assam state, police chief Mukesh Sahay said, adding the police suspected the United Liberation Front of Assam for the explosions. At the parade in Delhi, colourful floats depicted festivals from Indian states while the military displayed its armoury including tanks and supersonic missile systems. The country's Tejas fighter jet made its debut at the parade. A contingent from the United Arab Emirates forces also marched along with Indian soldiers at the parade, which ended with a flypast. Security personnel were stationed on buildings along the parade route with anti-aircraft guns. Other Indian cities and towns - particularly in the insurgency-hit Jammu and Kashmir and the country's financial hub Mumbai - were also on alert and held celebrations under heavy security.