Flights between Indonesia and Australia are disrupted as Bali's volcanic Mount Agung continues to send a plume of volcanic ash and steam more than 6,000 metres into the skies above the popular holiday island.
Ash from the eruption covered roads, cars and buildings near the volcano in the northeast of the island, while overnight a red glow of what appeared to be magma could be seen in photographs by Antara, the state news agency.
Indonesian authorities ramped up warnings in response.
"Since last night the eruption has been a magmatic type eruption, not phreatic," Sutopo, a spokesman for Indonesia's Disaster Mitigation Agency (BNPB), said in a Twitter message, referring to the switch from a steam-driven eruption to one with magma.
"That's what has caused the eruption to continue to produce smoke and dark volcanic ash."
AirAsia and Virgin Australia flights between Denpasar and Australia remained grounded on Sunday night.
Jetstar was forced to cancel numerous flights on Saturday and the following morning but was back on schedule by Sunday evening.
Qantas flights continued to operate.
Vulcanologist Simon Carn said on his Twitter account: "Summit glow at #Agung indicates magma likely at or near surface. Satellites also detected thermal anomalies overnight."
A live stream fixed on the mountain shows the summit continuing to smoulder as the sun set on Sunday.
Bali, famous for its surf, beaches and temples, attracted nearly five million visitors last year, but business has slumped in areas around the volcano since September when Agung's volcanic tremors began to increase.
Indonesia upgraded its Volcano Observatory Notice for Aviation (VONA) to red, its highest warning, and said the ash-cloud top could reach 6,142m or higher.
However, officials said the airport would remain open for now as the ash could be avoided.
"The volcanic ash has only been detected in a certain area," the airport and other officials said in a joint statement.
All domestic flights and the airport were operating as "normal" and tests for ash had been negative, it said.
The Australian government's Smartraveller service cautioned visitors on the island to monitor local media reports and follow the instruction of Balinese authorities as warning levels change quickly.
