Mount Sangeang Api in Indonesia erupted on Friday, spewing ashes in the air between 20,000 and 50,000 feet in the air and up to 15 kilometres across. The ash plume swept towards Alice Springs in Australia.
The eruption caused Qantas, Jetstar and Virgin Australia to cancel all flights between Australia and Bali. Among the cancelled route were Bali-bound planes from Melbourne, Darwin, Adelaide and East Kimberley. Also cancelled were Jetstar Asia trips between Bali and Singapore.
Authorities said the cancellation of flights could last for a few days, at the very least until Sunday. Deputy Prime Minister Warren Truss said it could take days before services between Australia and Indonesia return to normal depending on the wind and other conditions.
He added the ash could also affect flights from other airports, including Brisbane. Airlines cancel flights whenever volcanoes spew ash in the air because the live particles could damage aircraft engines.
The Civil Aviation Safety Authority warned Australian pilots and aviation operators about the danger of flying through or near the ash, but the decision is ultimately left in the hands of airlines.
Emile Jansons, manager of the Darwin Volcanic Ash Advisory Centre said, quoted by Reuters, "The volcano is undergoing a sustained, rather significant eruption at the moment."
He said the centre has been observing the volcano for the past 10 hours generating large masses of volcanic ash, but no one has a good handle on how the volcano would behave in the next 24 hours or more.
Since 1988, the Indonesian island where Sangeang Api is located has no permanent residence since the fled the place after the last eruption. Nearby farmers were ordered to vacate the area.
Sangeang Api is one of the 130 active volcanoes in Indonesia. Its first recorded eruption was in 1512 and the last was December 2012.