Some 150 personnel with two thermal drones have been deployed since Sunday morning, the head of local rescue agency Iwan Ramdani said, with the focus of the search around 100-150 metres of the crater rim.
"However, Mount Dukono continues to erupt and rain is also falling in the area. We carry out rescue efforts during intervals when there are no eruptions," Iwan told Reuters.
Mount Dukono, located in North Maluku province bordering the Pacific Ocean, began erupting on Friday, spewing ash as high as 10km. It has continued to erupt at a lower scale ever since.
The area around the crater was still blanketed in volcanic ash, Iwan said, adding that search covers area around 1.25km from the last known location of the victims.
Rescuers have found backpacks suspected to belong to the two Singaporeans. Survivors told police they were dead, police chief Erlichson Pasaribu had said.
Authorities on Saturday confirmed that one Indonesian hiker who had previously gone missing was dead.
Seventeen people, including seven Singaporeans and 10 Indonesians, survived the incident.
The Singaporeans will travel home on Sunday, Singapore's Foreign Ministry said in a statement.
Indonesia's volcanology agency reported at least three eruptions as of Sunday morning, with the highest spewing 1.3km of volcanic ash, it said in a statement.
The agency is still maintaining the third-highest alert level for Mount Dukono and bans any activities within four kilometres of the crater.
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