Indonesia's Mount Merapi volcano killed 18 people in another huge eruption on Friday, a hospital source said, as the government widened the danger zone and ordered new evacuations.

The latest deaths bring the total toll to more than 60 since the the country's most active volcano started erupting on October 26.

"The death toll rose to 18 people. Their bodies are badly burnt," said Sri Suyatini, a spokeswoman for Sarjito general hospital in Yogyakarta near the volcano on the central island of Java.

"We are treating now 58 people for burn injuries and resporatory problems due to the volcanic ash."

Government vocanologists said Friday's blasts were the biggest yet.

"This is the biggest eruption so far. The heatclouds went down the slopes as far as 13 kilometres (eight miles) and the explosion was heard as far as 20 kilometres away," volcanologist Surono said.

The exclusion zone was widened from 15 to 20 kilometres around the mountain and anyone living inside was ordered to evacuate their homes and shelters immediately, he said.

Some 100,000 people are already living in temporary shelters.

earlier related report
More evacuated as Indonesian volcano erupts again
Wukirsari, Indonesia (AFP) Nov 4, 2010 - Indonesia ordered thousands more people to evacuate Thursday as the country's most active volcano erupted again, shooting gas and ash into the sky and triggering a new aircraft exclusion zone.

Volcanologists said the "high intensity" eruption was the strongest yet from the 2,914-metre (9,616-foot) Mount Merapi, as officials revised the total death toll up to 44 from 36 who were killed on October 26.

"Today's eruption is bigger than yesterday's. Heat clouds and volcanic material were shot 10 kilometres (six miles) into the sky," said Kurniadi Rinekso, a government scientist in Yogyakarta, which lies south of the volcano.

An avalanche of heat clouds that can kill anything in their path streamed nine kilometres down the slopes of the volcano, a sacred landmark in Javanese tradition whose name translates as "Mountain of Fire".

Evacuees staying at an emergency shelter in Wukirsari village in Sleman district, about 20 kilometres from the volcano's peak, said it spat heat clouds and debris for about three hours after dawn.

Scientists however said it had erupted throughout the night but the scale of the blasts -- which reached almost as high as the altitude of cruising jetliners -- had only become visible after sunrise.

Officials said the number of people at safety shelters rose past 100,000 from 75,000 on Wednesday, when the official exclusion zone was widened from 10 to 15 kilometres around the volcano, taking in many more villages.

"The emergency shelters are now overcrowded," emergency response field coordinator Widi Sutikno said.

"We've started to move facilities and equipment from the previous shelters to the new locations," he added.

One mother in a shelter said her six-year-old daughter was traumatised by the eruptions.

"Every time she sees the mountain she cries and freaks out," the woman said.

An official said that including the October 26 eruption, 41 people had been killed "as a direct result of the eruptions" and three in related incidents, including a baby accidentally suffocated by her mother as she tried to flee.

Indonesia's transport ministry told pilots to stay at least 12 kilometres away from the rumbling volcano, spokesman Bambang Ervan told AFP.

The authorities kept in place a flight safety warning first issued on Tuesday, he said, and added the exclusion zone on a "recommendation from the volcanology office".

Malaysian budget carrier AirAsia said it resumed flights to the nearby cities of Yogyakarta and Solo Thursday morning after calling off eight flights on Tuesday and Wednesday.

SilkAir, the regional wing of Singapore Airlines, has cancelled four flights between Singapore and Solo since Tuesday, the company's staff said.

Indonesian President Susilo Bambang Yudhoyono on Wednesday visited people displaced by the volcano as the disaster-prone country struggles to cope with dual natural disasters following a tsunami off Sumatra on October 25.

The three-metre wave smashed into villages on the remote Mentawai island chain following a 7.7-magnitude earthquake off the coast, killing 428 people and leaving 15,000 homeless.

Another 74 people remain missing, feared dead.

Bad weather and poor communications on the undeveloped islands -- a legendary destination for foreign surfers -- have hampered efforts to bring food, shelter and medicine to the affected areas.

"We have to use rubber boats to reach isolated villages. We even have to swim to bring the boat over coral reefs," Indonesian Red Cross spokeswoman Fitriana Sidika said.

She said survivors were suffering from infections to untreated wounds, respiratory problems and malaria.

"They're living in unhygienic environment. We're coordinating with local government to relocate them to another place," she said from Bulakmonga hamlet on North Pagai island, where about 70 people were staying despite their houses having been flattened.

There was no news on the fate of three New Zealand yachtsmen who have not been heard from since the tsunami. They were believed to have been sailing towards the Mentawais on the night the three-metre wave struck.

The Indonesian archipelago has dozens of active volcanoes and straddles major tectonic fault lines from the Indian to the Pacific oceans.