Indonesia's most volatile volcano - one of 22 being closely watched following an increase in activity - has unleashed its most powerful eruption, spewing searing clouds of gas and debris thousands of feet into the air.
Almost all villagers living along Mount Merapi's rumbling slopes have been evacuated, some forcibly by camouflaged troops, though many have insisted on returning to their homes during the day to check on livestock and crops.
Monday's eruption was accompanied by several deafening explosions.
It comes as hundreds of miles away, rescuers try to get aid to victims of an 18ft-high tsunami that slammed into a group of remote islands off the coast of Sumatra on October 25, sweeping entire villages to sea.
The twin disasters, occurring simultaneously on opposite ends of the seismically charged country, killed almost 500 people in the last week, while severely testing the government's emergency response network.
In both cases, the military has been called in to help. There were no immediate reports of new casualties.
As massive clouds spilled from the volcano and billowed into the air - with no sign of slowing nearly two hours after the blast - debris and ash cascaded nearly two miles down the north-eastern slopes, said a spokesman, who is part of the team monitoring activity at the mountain that has already killed 38 people.
More than 800 miles to the west, boats and helicopters were ferrying aid to the most distant corners of the Mentawai Islands, where last week's tsunami destroyed hundreds of homes, schools, churches and mosques.
A military helicopter evacuated badly injured survivors who had languished in an overwhelmed hospital with only paracetamol to ease their pain, said Ade Edward, a disaster management official.
Among those evacuated was a baby girl born in a shelter after the tsunami and a 12-year-old girl with a life-threatening chest wound.