GNS Science has again raised the volcanic alert level on the island to level three out of six, following a minor eruption just after 8am.
It has also raised the aviation colour code to orange, which indicates a volcano is showing heightened unrest with increased likelihood of eruption, or an eruption is under way with no or only minor ash emissions.
GNS observed activity on the island off Bay of Plenty yesterday.
Duty volcanologist Yannik Behr said a further minor eruption happened about 8.10am today.
"Footage from our Whakatāne camera indicates that this morning's activity is very similar in size to what was observed yesterday.
"We noticed a vigorous steam-gas plume above the island at 8.10am. As we have no sensors on the island, we are relying on webcams and satellite imagery to assess the situation.
"Based on our limited information there were no clear indications of volcanic ash in the plume. If there were, it would be unlikely to reach the mainland under current wind conditions."
A minor eruption happened on Friday morning, when witnesses described smoke rising from the island.
A resident near the island told RNZ there was a "good eruption going on" with "big plumes smoke and ash".
By evening, however, there had been no other eruptions and the island's activity level was lowered.
In 2019, a deadly eruption of the volcano killed 22 people and injured 25 others.
The steam-gas plume above the island had reverted to more normal levels, and GNS Science volcanologists were continuing to monitor the volcano, Behr said.
Bay of Plenty Emergency Management said the harbourmaster had advised all vessels to avoid the area around the island.
