The decision in this regard was taken by the government within a week of the actor's family meeting Chief Minister, Pinarayi Vijayan, seeking a CBI probe into Mani's death, official sources said.
Ramakrishnan, Mani's younger brother, who had met the Chief Minister to press for a CBI probe into the actor's death, had said the family was not satisfied with the probe being carried out by the state police.
The 45-year-old actor, who had essayed various roles in south Indian films, was found in a serious condition at his farmhouse at Chalakudy and though he was rushed to hospital, his life could not be saved.
Mani was undergoing treatment for a liver ailment at Amrita Institute of Medical Sciences, where he breathed his last.