JAKARTA, Indonesia -- A volcano erupted on Wednesday morning on the same central Indonesian island as an earlier earthquake and authorities warned planes about volcanic ash in the air.

Mount Soputan in North Sulawesi province spewed ash 6,000 meters into the sky on Wednesday morning. No evacuations were immediately ordered but local disaster agency officials had distributed masks to residents, officials said.

A government volcanologist said it's possible the eruption was accelerated by the magnitude 7.5 earthquake in Central Sulawesi on Friday.

"It could be that this earthquake triggered the eruption, but the direct correlation has yet to be seen as there had been an increase in the Mount Soputan activity," Kasbani, the head of Indonesia's Volcanology and Geology Disaster Mitigation agency, told online news portal Tempo.

Kasbani, who uses one name, said volcanic activity had been increasing at Soputan since August and began surging on Monday.

An exclusion zone has been declared 4 km from the crater and extended to 6.5 km for the areas southwest of the crater, said Sutopo Purwo Nugroho, spokesman for the national disaster management agency.

Planes were warned of the ash clouds because volcanic ash is hazardous for their engines.

Meanwhile, the death toll from Friday's quake-tsunami disaster passed 1,400 on Wednesday, with time running out to rescue survivors and the UN warning of "vast" unmet needs.

Sutopo said the number of dead had risen to 1,407 around the ravaged seaside city of Palu, and 519 bodies had been already buried.

Authorities set a tentative deadline of Friday to find anyone still trapped under rubble, at which point-a week after this devastating double disaster-the chances of finding survivors will dwindle to almost zero.

According to the UN's humanitarian office almost 200,000 people need urgent help, among them tens of thousands of children, with about 66,000 homes destroyed or damaged by the quake and the tsunami it spawned.

Aid was slowly making its way into areas devastated by the twin disasters, with one neighborhood's residents clapping, cheering and high-fiving in their excitement on Wednesday at seeing a stopped truck laden with supplies.

"I'm so happy," said Heruwanto, 63, who goes by one name. He was clutching a box of instant noodles. "I really haven't eaten for three days."