Prime Minister Narendra Modi on Tuesday paid tribute to Iron Man of India Sardar Vallabhbhai Patel on his death anniversary. "The path he showed us will always inspire us to protect the unity, integrity and sovereignty of the country," the PM tweeted. Patel, a freedom fighter and a life-long Congressman, who became India's first home minister and deputy prime minister, is credited with unifying hundreds of princely states with the Union of India.