"Bangladesh government has taken steps to provide security to the minority Hindus, but unfortunately the Hindus have a feeling of insecurity and uncertainty about their future," Roy said, while participating in a discussion here on Wednesday night.
He said the Bangladesh government of Prime Minister Sheikh Hasina has formed an international tribunal to punish the "slaughterers who have killed thousands of people".
"During the partition of the country in 1947, (the then) East Pakistan had 29 per cent Hindu, but now it has reduced to 8 to 9 per cent," the governor said.
The discussion was arranged in connection of publication of Roy's book - "Ja Chhilo Amar Desh" (What was my country), a tale of exodus of minorities from what is now Bangladesh.
Roy, who elaborated how several massacres were taken place in erstwhile East Pakistan and acts of Pakistani Army and the then rulers, said that many people know about the Jallianwala Bagh Massacre in India but many people do not know about the more heinous massacre in Chuknagar (under Khulna district in Bangladesh).
"In the Jallianwala Bagh Massacre in 1919 around 1,500 people were killed but in Chuknagar massacre, the Pakistani Army and its associate Razakars butchered 10,000 unarmed Hindus by bullets, bayonets and stampede on May 20, 1971," he said.
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"Chuknagar massacre is one instance. In many places in the then East Pakistan several massacre took place and during Bangladesh liberation war such brutal mass carnage took an ugly turn."
"The mass atrocities were begun on Hindus in Noakhali in previous East Pakistan in 1946. With the active participation of Pakistani rulers, the atrocities and massacres on Hindus turned barbaric in 1950, 1964 and 1971. Besides massacre, mass looting, rape and killings forced over one crore Hindus to take shelter in India and lived with heavy poverty and deprivation," he said.
Roy, a former President of Bharatiya Janata Party unit in West Bengal, said that his book was not written to generate hate against the Muslims by the Hindus or not to make distance or create enmity between India and Bangladesh.
"The book was written only to say the truth. Many books were written, many films were made on the pre and post liberation period, but nowhere it was not elaborated why lakh of Hindu had forced to leave their ancestral homes in the then East Pakistan and took shelter in West Bengal."
"I believe, forgive by all means but never forget. The new generation must know what done against the minority Hindus in the then East Pakistan and why lakh of people had to take shelter in India," said the engineer turned politician turned governor.
Roy, was born in Kolkata but his ancestors belonged to Bangladesh's Brahmanbaria district. He said that some leaders backed by Pakistani founder Muhammad Ali Jinnah tried to merge Tripura with Pakistan instead of India.
He said: "After I wrote my first book - My People, Uprooted - in 2000, I was not allowed to visit Bangladesh as Dhaka did not give me visa but last year, I have visited Bangladesh thrice. I have a cordial relation with Bangladesh."
Renowned academician Arunoday Saha and Kolkata based publisher Sabitendranath Roy also spoke in the discussion.
The governor in his 384-page book also criticised former Prime Minister Jawaharlal Nehru and accused him for creation of Pakistan occupied Kashmir.
The septuagenarian writer also criticised Left parties for their role in India's partition.