Indonesian officials evacuated 11,000 villagers from around Mount Merapi on the island of Java today as lava and superheated clouds of gas poured repeatedly down the volcano's upper slopes.

The volcano's rumbling threatened Java with its second major natural disaster in ten days. The island province is still coping with the after-effects of an earthquake - its epicentre only 25 miles from Merapi - that killed nearly 5,800 people and left 340,000 people homeless and forced the UN to launch a major relief effort.

Vulcanologists have been recording increasing activity on Merapi for several weeks.

Today, thousands of local people were evacuated from hamlets near the peak. Local officials mobilised more than 40 trucks and cars to evacuate the villagers, taking them to temporary shelters including school buildings.

Mount Merapi, which looms over the earthquake plain, was put on red alert on May 13, when some 22,000 people were taken to safety, although most had returned by the time the quake hit two weeks later. The mountain’s lava dome has continued to swell since then, raising fears that it could suddenly collapse.

Bo Asplund, the UN’s humanitarian co-ordinator in Indonesia, said that aid was flowing to the quake victims and that needs would soon shift towards finding housing for those whose homes were flattened.

"From what I’ve seen in the field, the relief operation is certainly in full swing, I think the logistical bottlenecks are being overcome," Mr Asplund said in Yogyakarta, the main city in the quake zone. "I do not think there are still any villages that have not been reached, which was the case for a few days after the earthquake."

He said no more field hospitals were required, but there was a continuing need for medical supplies and specialist medical care. "In this disaster, given that it struck a part of Indonesia that is well organised and has a strong government, I think we will get to the recovery phase sooner and more quickly than if it had struck a different area," he said.

Indonesian health authorities with help from the UN Children’s Fund (Unicef) are to begin vaccinating more than 130,000 children under the age of 5. All adults in the quake zone are also to receive a booster dose of tetanus vaccine.

"We are racing against time and disease after two people were reported with tetanus," said Gandung Hermanto, head of the surveillance division at the health department in Bantul, the worst-hit district.

Tetanus usually starts from a contaminated cut or deep puncture wound. It is fatal in more than 30 percent of cases, with even higher rates in the developing world. At a US military field hospital, Lieutenant Eric Tausche said that many quake victims treated there had suffered injuries that could easily lead to tetanus.

"It’s a great concern anytime anyone comes here with an open wound," he said. "We’ve seen lots of compound fractures and soft-tissue damage. Everyone here with such an injury gets a tetanus shot."

Among the evacuees arriving at Kepuharjo high school, where more than 300 people have been staying since last night, women and children piled out of a truck which had collected them from the village of Petung, three miles from Merapi's peak.

Pailah, a 27-year-old who carried a bundle of clothes and pillows wrapped in a sarong, said that she had evacuated her two children, aged eight and six, because she was scared. "It was making noises and raining ashes," she said of the volcano.

Another woman, Sokirah, who fled Petung with her eight-year-old son, said: "I feel afraid it will explode."

But other villagers said that they would stay to look after livestock, and were confident they could escape in time if the lava dome did collapse.

"The evacuation is proceeding and will continue until late tonight," said Agung, a disaster relief official from Magelang district. "It is no longer a mere call for the people to evacuate, they now have to evacuate. We are not taking any chance."

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