Civil Defence has criticised members of the public who flocked to the beach after yesterday morning's tsunami warning was issued.
Bay of Plenty group co-ordinator Greg Wilson said that although the tsunami was not life-threatening, a failure to seek higher ground in future could be disastrous.
"One day, whether it's tomorrow or in a hundred years, there will be decent-size waves and there'll be casualties," Mr Wilson said.
He said a 1m wave did not sound large, but it was often kilometres long, and pushed a huge body of water ashore over several minutes.
After the first waves to arrive at East Cape were measured at under half a metre, Civil Defence downgraded the tsunami warning to a threat advisory.
At 4.30pm all warnings were cancelled.