No threat despite eruption at Anak Krakatau volcano: scientist

"Tremors from Anak Krakatau are still fluctuating but are still within the limits of the 'beware' status," volcanologist Anton told AFP, speaking from a monitoring post about 40 kilometres (25 miles) from the island-volcano.

"Even if a main (explosive) eruption happened, looking at the historical behaviour of the volcano there would be no threat to people living on the coasts of Java and Sumatra," he said.

The lava flowing from the crater is not visible from the main islands, so volcano-watchers chartering boats to see it should still remain three kilometres away, he warned.

Several volcanoes in Indonesia, which sits on the Pacific "Ring of Fire" where continental plates collide, have roared to life in recent weeks.