In their complaint, nephews of John, also a former state minister, alleged that a key member of a trust managing his assets did not provide him proper treatment when he fell ill last month. 74-year old John died on June 9 at a private hospital.
The complaint alleged that instead of taking John to a better facility in Kochi when he had fallen ill suddenly, he was admitted to a small hospital in Alappuzha, police said.
The matter was under investigation, a police official said.
The wife John had predeceased him and he is survived by a son.