KUALA LUMPUR Three dams and 10 water treatment plants in a Malaysian state have been closed to the public after an anonymous caller threatened to poison one of the dams, officials said today.

A spokesman for the Penang Water Supply Corp. said the Air Itam, Teluk Bahang and Mengkuang dams on northern Penang island have been closed since Friday as a precautionary measure.

But water in the state remained safe for consumption and there was no disruption to supplies, he told AFP .