The protesters numbering around 60 and affiliated to Kerala Union of Working Journalists (KUWJ) raised slogans condemning the attack and seeking stringent action against the culprits.
A reporter and a cameraman of the news channel were reportedly manhandled by a group of persons during a public function attended by CPI-M polit bureau member Pinarayi Vijayan at Mudhalakulam grounds here last evening.
Six persons were arrested in connection with the attack, police said.
Meanwhile, CPM leaders, including District Secretary P Mohanan, expressed regret over the incident.