Thousands are fleeing the island of Ambae in mass evacuations as the Monaro Volcano erupts.
GNS volcanologist Brad Scott flew over the island and told Larry Williams the volcano is chucking out lava bombs.
He said Monaro has been waking up for sometime but this explosion is more fiery than previous eruptions and the volcano is unpredictable.
"There's a summit at crater lake and in that crater lake there is a volcanic cone which has brewed since September that's chucking out lava bombs."
Mr Scott said evacuations are neccessary.
"It's a very hard call the volcano is capable of doing lots of things and keeping people safe is the number one priority for sure."
Thousands have already fled the island in mass evacuations.