A suspected RSS worker has been arrested in Kerala for allegedly pouring cow dung over award-winning filmmaker Priyanandanan T.R. on Friday in protest against his derogatory comment on Ayyappan, the deity at the Sabarimala temple.

Priyanandanan, 52, had just left his home at Vallachira in Thrissur city around 9am when a man walked up to him with a bucket of cow dung mixed with water and emptied it over his head.

“He then slapped me on the (right) ear and asked who did I think I was to comment against Ayyappan,” the Left-leaning filmmaker told The Telegraph.

An alleged RSS worker, Sarovar Vallachira, has been arrested on charges of assault. Sources said the suspect had fled to Kodungallur, 40km away, after the attack.

A state BJP general secretary, M.T. Ramesh, said the arrested man had no RSS links.

Priyanandanan said the attack had left him shaken: “I was not at some strange place but just a short distance from my home when this happened.” He said he would pursue the case against Sarovar, but didn’t believe the assailant was acting alone.

“This was a planned attack. I suspect they (Sangh parivar activists) had monitored me for a few days and knew exactly when I stepped out of home each morning,” the filmmaker said. He added: “One BJP leader had said at a public meeting that they would break my legs for my comment.”

Priyanandanan, whose Pulijanmam had won the National Film Award for best feature film in 2006, was accused of blasphemy after posting a Facebook comment on Ayyappan three weeks ago, at the height of the Sabarimala controversy over the entry of women of childbearing age.

A state BJP general secretary, B. Gopalakrishnan, had on January 12 warned that Priyanandanan would not be able to walk around even in Thrissur without police security because of the post.

When the post drew flak even from the general public, the filmmaker deleted it.

“I deleted the post realising I had made a mistake. But what happened today is an attack on free speech,” he said.

Asked if he would seek police security, Priyanandanan told this newspaper he wouldn’t. “To live and move under police security doesn’t make sense in a democratic nation.”

Chief minister Pinarayi Vijayan condemned the attack, blamed the parivar, and said: “This is proof of the growth of intolerance in Kerala.”

Hard-line Hindu organisations have been demanding an apology from Priyanandan for hurting religious sentiments. The BJP had threatened a police complaint.

The Sabarimala temple, which closed on January 20 after a two-month pilgrimage season, will open for the five-day monthly rituals on February 12.