An Indonesian volcano spewed another column of hot ash Friday, a vulcanologist said.

Mount Sinabung in North Sumatra province erupted for the first time in about 400 years Sunday and Monday, forcing 30,000 people to flee their homes to temporary shelters.

About 10,000 people had returned to their villages to attend crops when the latest eruption occurred, officials said.

'There was dark smoke and the roar was heard within the radius of eight kilometres,' said Surono, head of the Center for Volcanology and Geological Disaster Mitigation, who like many Indonesians goes by one name.

He said he had advised local authorities to order villagers to evacuate overnight when signs of an impending eruption were detected.

'We hope it was the last eruption and residents can go back to their homes in the coming days,' he said.

Indonesia has about 500 volcanoes, with nearly 130 of them active and 69 listed as dangerous.