JAKARTA, Sept 24 — Indonesia has raised an alert for a volcano on the island of Bali to its highest level amid warnings of a possible eruption that could threaten air travel and tourism.

An increase in volcanic activity at Mount Agung, in the island’s east, prompted authorities to raise the alert level on Friday evening, warning that an eruption was imminent. National Disaster Mitigation Agency spokesman Sutopo Purwo Nugroho said an evacuation had been ordered, affecting thousands of people living within a 12-kilometre radius from the volcano.

While Bali’s international airport remains open, the Volcano Observatory Notice for Aviation said earthquake activity had been "increasing rapidly” and a small hotspot had been detected although no ash cloud was visible. A spokeswoman for Australia’s Qantas Airways Ltd. said its meteorology team was monitoring activity but services had not been affected.

Australia’s Department of Foreign Affairs and Trade issued travel advice Friday, warning of recent increased volcanic activity. The advice, via its Smartraveller website, said an eruption of Mount Agung could impact air travel in the region. — Bloomberg