An Indian artist has been assaulted in a gallery in the capital, Delhi, where he is exhibiting a number of nude paintings.
Pranava Prakash said five men barged into the gallery in the Noida district on Sunday, saying the pictures were "against Indian culture".
He said he was thrown to the floor and a number of pictures were damaged.
Hardline Hindu groups have in the past protested over art works they say offend their beliefs.
The attack also comes in the wake of an intensified debate over artistic free speech, with controversial UK writer Sir Salman Rushdie abandoning plans to attend a literary festival in Jaipur amid security concerns.
Mr Prakash told Agence France-Presse news agency: "Five guys came in on Sunday and started yelling at me, saying, 'Your paintings are against Indian culture, we cannot tolerate them'.
"They slapped me twice, threw me to the floor and then began pulling down the paintings, damaging three of my pictures."
The nude paintings in the Espace Alternative Gallery include depictions of Bollywood star Vidya Balan, Pakistani actress Veena Malik and model Poonam Pandey.
The latter painting features Ms Pandey with words written on her bosom, while Ms Malik appears with the Pakistani flag painted on her back.
Mr Prakash said: "There is a certain section of people who think they alone are the custodians of Indian culture, and anyone who disagrees with them is the enemy."
Hardline Hindu groups have protested in the past over art works they regard as offensive, including by late artist MF Husain.
Valentine's Day has also come under attack for being anti-Hindu.
Sir Salman lashed out at extremists who he said were undermining free speech after an attempt to address the Jaipur festival by video-link were abandoned amid threats of violence by Muslim hardliners opposed to his book, The Satanic Verses.
- BBC News