The volcano that killed 33 people this week began erupting again, though there were no reports of new injuries or damage. Mourners held a mass burial Thursday during a lull in Mount Merapi's rumblings.
Elsewhere in Indonesia, rescuers searching islands ravaged by a tsunami off western Indonesia raised the death toll to 343 Thursday as more bodies were found and said the number is likely to climb higher because hundreds of missing people may have been swept away.
President Susilo Bambang Yudhoyono was to meet Thursday with survivors of the twin catastrophes, which struck within 24 hours in different corners of the seismically charged region, severely testing the nation's emergency response network.
Officials say a multimillion-dollar warning system installed after a monster 2004 quake and tsunami broke down one month ago because it was not being properly maintained.
In the tsunami-ravaged Mentawai islands, search and rescue teams – kept away for days by stormy seas and bad weather – found bodies on the roads and beaches, according to Harmensyah, head of the West Sumatra provincial disaster management center.
The tsunami hit Pagai Utara, one of the four main islands in the Mentawai chain located between Sumatra and the Indian Ocean. Huge swaths of land were underwater and houses lay crumpled with tires and slabs of concrete piled on the surrounding sand.
Ferry Faisal, of the West Sumatra provincial disaster management agency, raised the official toll Thursday to 343 from 311 earlier in the day. He said 338 people are still missing.
Harmensyah said the teams were losing hope of finding those missing since the wall of water, created by a 7.8-magnitute earthquake, crashed into the islands on Monday.
"They believe many, many of the bodies were swept to sea," he said.
On Thursday, more than 100 survivors crowded into a makeshift medical center in the town of Sikakap on Pagai Utara. Some still wept for loved ones lost to the 10-foot (three-meter) wave as they lay on straw mats or sat on the floor, waiting for medics to treat injuries including broken limbs and cuts.
Hermansyah, a local fisheries ministry official who survived the earthquake and wave that hit Sikakap because he was on higher ground, quickly formed a rescue coordination committee and began traveling to other areas, finding several villages flattened.
"Not even the foundations of houses are standing. All of them are gone," said Hermansyah, who like many Indonesians uses a single name.
He said the devastation he saw indicates the wave could have been higher than reported in some areas ó perhaps more than 20 feet (six meters) high.
About 800 miles (1,300 kilometers) to the east in central Java, Mount Merapi began spewing hot clouds of ash again at around 4:30 p.m. Thursday, according to the Indonesian vulcanology agency Subandriyo.
Most residents have been evacuated from the area. It was unclear whether the new activity was a sign of another major blast to come. Tuesday's eruption killed at least 33 people and injured 17, said Agustinus, a doctor at the local health department.
Residents from the hardest-hit villages of Kinahrejo, Ngrangkah, and Kaliadem - which were decimated in Tuesday's blast - crammed into refugee camps. Officials brought surviving cows, buffalo and goats down the mountain so that they wouldn't try to go home to check on their livestock.
Thousands attended a mass burial for 26 of the victims six miles (10) kilometers from the mountain's base. They included family and friends, who wept and hugged one another as bodies were lowered into the grave in rows.
Among the dead was a revered elder who had refused to leave his ceremonial post as caretaker of the mountain's spirits. He was buried in a separate funeral Thursday.