Mount Kelud, considered one of the most dangerous volcanoes on the main island of Java, spewed red-hot ash and rocks high into the air late yesterday night just hours after its alert status was raised.
TV images showed ash and rocks raining down on nearby villages, while AFP correspondents at the scene saw terrified locals covered in ash fleeing in cars and on motorbikes towards evacuation centres.
A man and a woman, both in their 60s, were crushed to death after volcanic material blanketed rooftops, causing their separate homes in the sub-district of Malang to cave in, National Disaster Mitigation Agency Spokesman Sutopo Purwo Nugroho said.
Some 200,000 people in a 10-kilometre (six-mile) radius from the volcano were ordered to evacuate, according to national disaster officials, though many tried to return to their homes to gather clothing and valuables - only to be forced back by a continuous downpour of volcanic materials.
More From This Section
"A rain of ash, sand and rocks is reaching up to 15 kilometres (nine miles)" from the volcano's crater, Nugroho said.
Virgin Australia said it had cancelled all its flights to and from Phuket, Denpasar, Christmas Island and Cocos Island today, saying in a statement that "the safety of our customers is the highest priority" and that the airline would keep monitoring the plume.
"About two hours in, the pilot announced over in Indonesia there was a volcano that erupted and that we were turning the plane back," she told AFP, adding they were still in Australian airspace at the time.
"We will have to call them this afternoon for rescheduling, but I doubt we will be travelling soon," she said.
A spokeswoman for Australian airline Qantas said that yesterday flights between Jakarta and Sydney had been pushed back to tomorrow.
"Flight paths from Australia to Singapore have been altered as a result of the volcanic ash cloud in Java," she said.