An Indian-born American economist has said that Christian leaders in India should "look into their own history... and relax a bit" when it comes to criticising alleged Hindu conversions.

Since Prime Minister Narendra Modi came to power last May there have been concerns about an increase in attacks on religious minorities, both Christians and Muslims, and reports of forced conversions to Hinduism.

But Jagdish Bhagwati, who is professor of economics and law at Columbia University, said in an interview with NDTV: "There are a few crazy people on the Hindu side who feel we should re-convert. How much does it amount to? Very little. I urge these Christian leaders to look into their own history of conversion... Hindus are not into conversion in any substantial way at all. I would just clarify and say look at your own history and relax a bit."

The Evangelical Fellowship of India reported last week that there had been around 600 violent attacks on minorities since Modi came to power – most recently the rape of an elderly nun at a convent in West Bengal this month.

Christians both nationally and internationally have condemned the attacks, which are seen as the result of a rise in Hindu nationalist sentiment in the country.

Prominent Christian commentator and retired police commissioner, Julio Ribeiro, wrote in a column for the Indian Express: "I feel threatened, not wanted, reduced to a stranger in my own country."

Responding to Ribeiro's comments Bhagwati said: "When I saw now he feels [he is] on the hit list, I could not believe what I was reading."

In an opinion piece for Livemint this weekend Bhagwati said that fears about the threat to Christians were a "false alarm". Explaining his position, he said that his wife had converted to Christianity and a number of his family members are Christians and he had attended a Christian school.

"So, if there was anything to the Christian fears today, I should be the first to join the protests," he wrote. "But the truth is that these fears are totally groundless and are, at best, a product of a fevered imagination."

In his interview with NDTV, Bhagwati condemned the inflammatory language used by the leader of the Hindu nationalist group RSS, Mohan Bhagwat – who recently said that Mother Teresa's work for the poor had the "ulterior motive" of conversion to Christianity.

But he added: "We cannot be responsible for every crazy statement made by somebody, no matter how influential he might be.

"I admire the Christian community but how many people are aware that the Catholic Church has been defending assault on young boys, right, pederast basically, so do I say that Catholics should continuously denounce that? I'm not interested in who says what. We really need to relax a bit."

Bhagwati also asked Christian leaders: "If you think you can convert, why do you object to other people saying they can convert?" adding that he personally did not "believe in a Hinduism that converts".