Authorities in the western Indian state of Gujarat state have banned a controversial book on Pakistan's founder Mohammed Ali Jinnah. The book has been written by Jaswant Singh, an expelled leader of the Hindu nationalist main opposition party BJP. The BJP government in Gujarat said it banned the book for its “defamatory references” to Vallabhbhai Patel, India's first home minister. Patel is a political icon in his home state of Gujarat. “The book has been banned because it contains defamatory references regarding Vallabhai Patel who is considered as the architect of the modern India,” a statement by the Gujarat government says. “It is a bid to defame Patel by distorting historical facts. So, the state government has decided to ban the book with immediate effect for wider public interest.” Jaswant Singh said he was “saddened” by the banning of the book in Gujarat. “The day we start banning books, we are banning thinking,” he said. Senior BJP leader Kailash Sarang Friday demanded that the book should be banned in the whole country. Talking to Press Trust of India (PTI), Sarang said the biggest mistake committed by Jaswant Singh was to unnecessarily heap praise on Jinnah. He said BJP was a responsible political party and no leader from it could be given permission to praise someone who was responsible for the Partition. Jaswant Singh's book examines the role of Congress party leader and the country's first Prime Minister, Jawaharlal Nehru, and Patel in the partition of India in 1947. Jaswant Singh, a 71-year-old party veteran who has served as finance and external affairs minister in BJP cabinets, said he was “saddened” by his expulsion. “It saddens me even more that I have been expelled on grounds of writing a book,” he said. Singh has said that his book is a “purely academic exercise, which should be read and understood.” Analysts have criticised the BJP for sacking Singh over a book. “Jaswant Singh's book is a serious academic exercise, one long overdue. It is complicated, full of internal tensions. A serious political party should have space for that,” wrote political scientist Pratap Bhanu Mehta in The Indian Express. “In expelling Jaswant Singh the BJP has confirmed the fears of its worst critics: that the party is nothing but a party founded on endless resentment that makes it inherently insecure and anti-intellectual.” The Times Of India daily said Singh's expulsion raised questions about free thinking and free speech in cadre-based, ideology driven parties. “Surely it is not impossible for a political outfit to function without asking members to always agree with party views,” the newspaper said. The Hindu says it is for “historians to evaluate the scholarly merit of Mr Singh's work.” “But who is to say that a political figure, especially when he or she is out of power, is not to dabble in such sensitive areas,” the newspaper wrote.