A 20cm tsunami generated by a huge earthquake in Chile hit New Zealand’s eastern Chatham Islands early this morning and officials warned that bigger waves were to follow.

The tsunami racing across the Pacific Ocean towards Hawaii and Asia was triggered by an 8.8 earthquake that rocked Chile early this morning. Roger Bilham, a professor of geological sciences at the University of Colorado, calculated that at mid-ocean, the mass of water would be hurtling toward Hawaii at 200 metres per second, or 720km/h.

“Mid-ocean, the wave is travelling at around the speed of a jet plane,” Prof Bilham said.

“The amplitude of the wave is small when it’s mid-ocean, but it may rise to five to 10 meters when it reaches Japan or the Philippines,” he said.

A huge arc of nations around the Pacific, from New Zealand to Japan, have gone on tsunami alert, while sirens have sounded warnings of destructive waves around Hawaii for the first time in 16 years.