Traditional Indian troubadours have been attacked for singing songs about Jesus and Allah, as rightwing Hindu groups labelled them “traitors” to their faith.

Balladeers of the Carnatic tradition - a south Indian musical style originally performed by Hindu mystics since the 17th century - were threatened after two leading exponents of the craft took part in interfaith events.

TM Krishna and OS Arun were targeted by fringe Hindu groups after the first tweeted that he would be expanding his range of religious songs to include odes to other faiths, while the second was accused of “collaborating with a stooge of the Vatican" after announcing he would perform at a concert organised by a Christian group in Chennai.

The row reflects the emboldening of fringe Hindu fundamentalist groups under the since Narendra Modi and his Hindu nationalist BJP party assumed power in 2014.

Mr Arun pulled out of the Chennai concert, citing personal reasons and the incident is the latest in what many see as a vicious campaign against folk musicians in the state of Tamil Nadu and other parts of south India.

Mr Krishna said: “Musicians have been attacked for singing some Carnatic songs on Jesus. I felt we need a response because if we buckle to this kind of 'goondaism' [gangsterism], everything is over.