The police in Papua New Guinea have detained three men suspected of contaminating the water system in Mt Hagen with engine oil.
The water supply was shut down since Monday when the Water Board discovered the oil had been poured into the main chambers which supplies water to residents.
The Provincial Police Commander for the Western Highlands Province Kaidlo Ambane says they are investigating the matter but believe the culprits may have been retaliating against actions taken by the board.
"I think they probably have a grievance with the PNG Water Board for some non-payment of claims as a land owner or for some jobs that they did for the water board and there was no payment or delays. And to this frustration they poured the oil in to the water."