Local communities have been told to stay indoors and international flights have been diverted as the cloud of ash reached 60,000 feet.
Mount Tavurvur, which destroyed the local town of Rabaul in 1994 when it erupted in tandem with Mount Vulcan, started to show signs of life early this morning.
There are currently no reports of injuries or damage, but people are being encouraged to stay in their homes and listen for updates on the radio.
Some have left Rabaul and moved elsewhere while the volcano continues to show signs of activity.
The Australian government has issued a warning against travelling to the country and Qantas has confirmed that three of its flight routes have been diverted.
Cyndee Seals from Darwin-based The Volcanic Ash Advisory Centre said: “The eruption was to 60,000 feet (18,000 metres), which is flight level…we expect [the ash] to clip the edge of Australian airspace later today, but we don’t expect ash over Australia.”
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