An impressive display of armour and unmanned aerial vehicles recently added to India's military prowess was on full display at the 63rd Republic Day parade on Thursday that also showcased the country's rich heritage.

The early morning chill did not deter people along the 8-km-parade route as they gathered on both sides of the majestic Rajpath, the country's ceremonial boulevard facing the Raisina Hills, and cheered the contingents as they went past portraying the diverse culture of the country.

The well-turned out and synchronised military and police formations led by General Officer Commanding (Delhi) Lt Gen V K Pillai marched proudly to the lilting tunes of bands through the Rajpath where President Pratibha Patil, who is the Supreme Commander of Armed Forces, took salute.

The impressive march-past was watched by Chief Guest Thai Prime Minister Yingluck Shinawatra, Vice President Hamid Ansari, Prime Minister Manmohan Singh, Defence Minister A K Antony, UPA Chairperson Sonia Gandhi, Marshal of Air Force Arjan Singh and top political and military brass.

Police and other para-military forces turned Delhi into a a virtual fortress for the Republic Day celebrations as helicpoters scanned from air, snipers kept a hawk-eye vigil from rooftops and armed personnel at every nook and corner provided a ground-to-air security apparatus.

Minutes before the parade began, Singh, Antony and chiefs of Army, Navy and Air Force laid wreaths at 'Amar Jawan Jyoti', an eternal flame in the memory of those who laid down their lives while defending the nation.

After the customary 21-gun salute and unfurling of the national tricolour, President Patil presented Ashok Chakra - the highest peacetime gallantry award - posthumously to Lieutenant Navdeep Singh who died foiling an infiltration attempt by Pakistan-based terrorists along the LoC in Jammu and Kashmir.

Then, four Mi-17 helicopters zoomed in from skies on the western side showering flower petals on thousands of spectators, signalling the start of the impressive parade followed by winners of Param Vir Chakra, highest war-time gallantry award, and Ashok Chakra and mounted columns of 61 Cavalry.

The Army showcased its impressive weaponry which included T-72 tanks, Carrier Motor Tracked vehicle, Smerch missile Launcher, Multi Barrel Rocket System 'Pinaka' and Full Width Mine Plough.

It also displayed the NBC (Nuclear- Biological-Chemical) Chemical Purification System and Jammer Station. Demonstrating its air power, Army's also conducted a flypast of three indegenously made advanced light helicopters Dhruv.

The Army contingent from Parachute Regiment, Bengal Engineer Group, The Brigade of the Guards, Kumaon Regiment, Assam Regiment, Mahar Regiment and Gorkha Rifles marched to the tunes of 'Arjuna', Thimmaya, 'Gangotri' and 'Veer Gorkha' military numbers.

The next to follow were smartly-dressed Navy personnel and then the Air Force contingent, led by Flight Lieutenant Sneha Shekhawat, marching to the tunes of 'Jai Bharati' and 'Air Battle'.

The Navy showcased models of the Delhi Class guided missile destroyer and IL-38 (Sea Dragon) Long-Range Maritime Reconnaissance aircraft.

The 3,000-km-range nuclear-capable Agni-IV missile, successfully flight tested in November last year, stole the limelight as people cheered and clapped when the weapons system's model came near them.

Commentaries gave an insight into the capabilities of the sophisticated missile system. The DRDO also put on display for the first time the 150- km range Prahaar tactical battlefield support missile and the Rustom-1 Unmanned Aerial Vehicle (UAV).