An eminent UK-based anthropologist who was deported on arrival at Thiruvananthapuram airport early on Thursday despite having a valid research visa has suggested the government action may have been related to his having a “couple of old Pakistan visas”.

The deportation of University of Sussex professor Filippo Osella, who has extensively researched Kerala society and had come to attend a conference, has evoked widespread condemnation from academics, who have underlined the 65-year-old was “non-controversial” and “never involved himself in political issues”.

Many, including the Kerala CPM, have sought an explanation from the central government which has been silent so far.

On Friday, Osella said in a statement to The Telegraph that the “deportation might have to do with something else, such as a couple of old Pakistan visas which are normally treated with some surprise every time I show my passport to immigration officials, but never came in the way of being allowed to cross the Indian border”.

“I am a South Asia specialist — indeed, I am a professor of anthropology and South Asian studies at the University for Sussex (UK) — and as well as working in South India, over the years I have also conducted some research and attended conferences in Sri Lanka and Pakistan,” he said.

Kerala CPM secretary Kodyeri Balakrishnan said: “He (Osella) has visited Kerala several times over 30 years as part of his research on Kerala’s socio-cultural changes. Along with registering our protest, I urge the central government to give an explanation on this action.”

Osella, who has also worked on reforms and philanthropy in Islam, had arrived on an Emirates flight from London via Dubai to attend a conference on livelihood issues of coastal communities. He was one of the key organisers of the two-day seminar, which got under way in Thiruvananthapuram on Friday.

On arrival, he was whisked away from the aircraft by a “government official” and taken to an immigration desk where his passport was checked and fingerprint scanned. He was told he was being deported as instructed by “higher authorities”, an academic said.

“I was in complete shock because I had a valid research visa issued by the government of India, and once I asked the immigration supervisor and officers as to why I was being deported, I was refused any explanation. In fact the immigration officers refused to talk to me altogether, beyond repeating a couple of times that this was a decision from the Indian government, and could not discuss it or talk about it,” Osella stated, adding he hoped it would not be his last trip to Kerala.

“I am utterly shocked and saddened… over the years Kerala has become a second home to me, a place whose culture I love deeply, and where I have countless friends. I have been animated by a passion for understanding the fast-paced transformations of Kerala, one of the most dynamic and culturally rich states in India,” Osella said.

Airport immigration has not issued any statement.

The conference has been organised by the Inter-University Centre for Alternative Economics of the University of Kerala, the Cochin University of Science and Technology, and the University of Sussex.

T.T. Sreekumar of the English and Foreign Language University, Hyderabad, wrote on Facebook: “I was the respondent for Filippo’s paper on communication technologies and artisanal fishers in Kerala. His paper will now be presented by his colleagues. I will miss him….”

Sindhu Maria Napoleon, a research associate at IIT Madras, wrote: “If this is going to be the fate of good scholars, I don’t know where we are heading.”