HelmudHontong, deputy regent of Indonesia’s remote Sangihe islands, died during a flight last Wednesday.
Rights groups say his death falls into a pattern of violence against people threatened for standing up for environmental rights.
But police say an initial post mortem examination points to a natural death.
The fifty eight-year-old politician appeared in good health before his flight on Bali island but his aide who was travelling with him said he began feeling dizzy twenty minutes into the journey.
