Jakarta, Feb 1 (IANS): Eleven people were killed and three others injured Saturday on being hit by hot ash from the re-eruption of the 2,475-metre-high Mount Sinabung volcano in North Sumatra, Indonesia, officials said.

"Eight corpses have been identified, while three others are on their way to a Kabanjahe general hospital," Sutopo Purwo Nugroho, spokesman of the national disaster agency, told Xinhua.

There may be more victims at the scene. But they could not be evacuated as they were in the pathway of hot ash, three km from the craters, he said.

Most of the dead were high school students who were on a journey to see the re-eruption of the volcano, while some were local villagers, said Sutopo.

An official said the injured were being treated in intensive care at a hospital.

Mount Sinabung erupted Saturday, sending hot rocks and ash up to 2,000 metres into the air. A dangerous zone of five km remains in place.

"Despite the dangerous zone declared, there are still many residents entering the zone," he said.

The volcano erupted three times during the day, spewing columns of ash about two km into the air and spreading hot rocks and ash over a 4.5-km radius.

Indonesia is enduring one of the longest series of volcano eruptions in more than 30 years, with the authorities forced to deal with a rising number of refugees in North Sumatra. More than 31,000 people have been displaced, officials said.

Mount Sinabung rumbled to life last September after remaining quiet for 400 years. It has erupted on and off since then but the frequency of eruptions increased in November and December last year.