JAKARTA: Indonesian authorities shut five airports on Friday, including on the popular holiday islands of Bali and Lombok, because of a volcanic eruption, a spokesman for the airport operator said.

"I can't say at this time how many passengers have been affected," said Farid Indra Nugraha, a spokesman for airport operator Angkasa Pura 1.

National flag carrier Garuda Indonesia cancelled all its flights to and from the four airports, it said on its official Twitter account.

"Bali is our second largest hub and this will also affect our international connecting flights," said Ikhsan Rosan, a spokesman for the airline.

Mount Raung in East Java has been erupting for nearly a week, forcing the cancellation of a number of flights to and from Australia.