The Free Media Movement has charged the police had acted beyond its powers when it arrested a journalist, Dineth Kumara.
In a statement, the FMM said the Kurunegala district correspondent for Sri Lanka Rupavahini Corporation was taken into custody while on duty, taking pictures outside Bingiriya police on 30 November.
Kumara has alleged that he was abused and assaulted inside the police station.
He said he had gone there to report on the summoning of persons, who had provided him with information, for an inquiry on a complaint by a party about whom he had reported on previously.
The journalist has since been released on bail by the Hettipola magistrate.
The FMM urged the authorities to conduct a proper inquiry and ensure justice for him.