TANAH KARO: An Indonesian volcano that was quiet for four centuries shot a new, powerful burst of hot ash more than 10,000 feet (three kilometres) in the air on Friday, sending frightened residents fleeing to safety for the second time this week.

The tremor from the eruption - the strongest so far - could be felt five miles (eight kilometres) away.

"This was a big one!" said 37-year-old Anto Sembiring, who abandoned his coffee shop not far from the crater's mouth to join hundreds of others near Mount Sinabung's base. "We all ran as fast as we could ... Everyone was panicking."

The eruption of Mount Sinabung on Sunday and on Monday - which caught many scientists off guard - forced 30,000 people living along its fertile slopes in North Sumatra province to evacuate to cramped emergency shelters in nearby towns.

Many started returning to their mountainside homes as activity started to wane, saying they wanted to tend to their vegetable farms and rice fields and to reopen small businesses.

A new alert was issued several hours before on Friday's blast.

Some people trudged back down the slopes, carrying blankets, clothes and food, but others insisted on staying, even after the new explosion, which caused the entire mountain to shake for five minutes.

"We're not going anywhere," said Razia Barimbing, who was among 50 men refusing to budge, saying they had to protect abandoned villages a few miles (kilometres) from the crater's mouth against looters.

"It's so sad to see this," said the 35-year-old farmer, pointing to the white dust blanketing houses, gardens and even livestock. "We just want this to be over, so we can pull our lives back together, and get our children back in school."

 The air was thick with the smell of sulfur and, despite a soft drizzle, heavy smoke limited visibility to just a few yards (meters). Some small domestic hopper flights had to be diverted, according to Bambang Ervan, the transportation ministry's spokesman.

Associated Press