India honored six security officers who were killed while responding to the attacks on Mumbai with the country's highest peacetime award during Republic Day celebrations Monday. President Pratibha Patil presented the Ashok Chakra medals to the widows of the officers during the traditional celebrations in the capital, New Delhi. Among those honored were Hemant Karkare, the head of Mumbai's antiterror squad, and two commandos who were killed while trying to end the gunmen's three day siege in November that killed 164 people and nine attackers. Gopal Ombale, a policeman who charged the gunmen armed just with a baton, was also given the award. His actions led to the capture of the lone-surviving gunman. India celebrated Republic Day on Monday with a grand military parade in New Delhi held under tight security conditions, two months after the terror attacks on Mumbai. The center of New Delhi was virtually shut down for Monday's celebrations, which attracted large crowds, and security was focused on areas close to the parade route such as metro stations and shopping centers. Federal Home Minister P. Chidambaram had ordered all 28 Indian states, including the seven restive northeast provinces and disputed Kashmir, to be on high alert. In Mumbai, a martial arts trainer scaled the 490-foot (150-meter) tall Shreepati arcade building to pay tribute to victims of the attacks. In New Delhi, dozens of roadblocks were set up across the city and some 20,000 police were on the streets. On Sunday, police said they had prevented a planned attack on New Delhi by killing two Pakistani militants on the outskirts of the city. Brij Lal, a senior police officer in Uttar Pradesh state, said an anti-terrorist team chased a car carrying the men towards the capital before they intercepted it in the suburb of Noida. Police said they found two AK-47 assault rifles and five hand grenades in the car. Indian Prime Minister Manmohan Singh missed Monday's events after undergoing major heart surgery. Bejewelled elephants that have been a highlight of Republic Day festivities for decades were banned from this year's parade due to fears about their unruly behavior and animal rights concerns. Among the military hardware on show were locally built T