Arupjyoti Saikia, a professor of history at IIT Guwahati who was questioned by the National Investigation Agency (NIA) on Saturday, has been asked to present himself for another round on Monday.

The NIA has not officially disclosed the reason behind questioning the 52-year-old Saikia, considered one of the most distinguished and respected historians in the country.

Saikia, who has researched the economic, environmental and political history of modern Assam, has written books such as The Unquiet River: A Biography of the Brahmaputra, A Century of Protests: Peasant Politics in Assam since 1900 and Forests and Ecological History of Assam, 1826-2000.

Himanta Biswa Sarma, BJP leader and one of the most powerful ministers in Assam, had said last month that the government had found the involvement of a leading academic in inciting the violence during the anti-Citizenship Amendment Act (CAA) protests in the city.

The NIA is apparently probing alleged links between leaders of the Krishak Mukti Sangram Samiti, a peasant organisation formed by RTI activist Akhil Gogoi, and Maoist groups. Gogoi is in judicial custody after being arrested for protesting against the CAA and charged with sedition.

Saikia’s lawyer (counsel) Santanu Borthakur, said: “It’s still unclear why he was asked to appear before the agency. Things will become clear only on Monday.”

KMSS leader Bhasco De Saikia told The Telegraph: “This is what governments do. They are branding leaders as Leftists and Maoists and putting them behind bars only to gag the anti-CAA movement. Even an academic like Arupjyoti Saikia has not been spared.”

On Sunday, several scholars and academics issued the following statement on the ordeal of Arupjyoti Saikia:

“We, a group of Indian scholars and academics from across the country, write in distress and with concern with regard to the ongoing ordeal of Professor Arupjyoti Saikia. Professor Saikia is one of the country’s most distinguished and respected historians. The author most recently of a landmark history of the Brahmaputra River, he has also written significant works on forest and agrarian history.

“For his contributions to scholarship, Professor Saikia is hugely admired, indeed venerated, in his native Assam. He also has a very high reputation nationally and even internationally, with his scholarship recognised by a prestigious fellowship from Yale University.

“Professor Saikia is an adornment to the literary and intellectual world of Assam and of India. He is also an individual of high moral character; gentle, soft-spoken, and utterly non-violent. His devotion to his students at IIT Guwahati is exemplary.

“That a scholar of such standing, and a human being of such decency, has been called for intensive grilling by the National Investigative Agency is deeply distressing. We urge that the NIA treat him with the dignity and respect he deserves, and allow him to continue his professional work unimpeded.”

The signatories to the statement include Sukanta Chaudhuri, professor emeritus, Jadavpur University; Ramachandra Guha, historian and columnist; Partha Chatterjee, former director, Centre for Studies in Social Sciences; Pratap Bhanu Mehta, academic and columnist; Samantak Das, Jadavpur University; Srinath Raghavan, Ashoka University; Supriya Chaudhuri, professor emerita, Jadavpur University; Nandini Sundar, Delhi University; Nivedita Menon, JNU; and Enakshi Bhattacharya, IIT Madras.