Mount Agung was pictured sending up a billowing ash cloud in Bali earlier after a period of relative calm and only intermittent eruptions.
The Bali volcano erupted at 5.54pm local time on the holiday island, according to Indonesia’s National Agency for Disaster Management (BNPB).
BNPB spokesman Sutopo Purwo Nugroho said ash rained down on villages of Kubu and Tulamben near popular dive sites with impressive reef.
But he confirmed that the airport is operating normally and the ash cloud had not led to the delay or cancellation of flights.
The Bali volcano has been intermittently sending up clouds of volcanic ash since Mount Agung first erupted in November.
In late November, Bali was put on high alert when the volcano erupted and sent ash columns into the sky. Cold lava also poured down the volcano’s slopes.
Since then the eruptions of ash have been on a much smaller scale. Today’s eruption was unusually large and brought back fears of a bigger eruption.
It is not known if a major eruption could happen but the authorities have evacuated villages to prevent a repeat of the deadly last eruption.
The last time the Mount Agung erupted in 1963, people had just minutes to flee and more than 1,100 people were killed.
Mount Agung remains under the highest possible alert, which is known as level four or Awas.
The danger zone covers a radius of 6km from the summit of the volcano. Earlier this month, the size was reduced from an up to 10m radius.