Nina Rao

A massive volcanic eruption has claimed the lives of at least three hikers on Indonesia's Mount Dukono in Halmahera Island.

The volcano erupted on Friday, blasting a thick pillar of ash and rock nearly 33,000 feet into the sky.

Among the dead are two Singaporean nationals and one Indonesian citizen.

Authorities say as many as 20 hikers were trapped near the crater when the eruption began.

While a climbing ban had been in place for weeks due to increased activity, officials note that the mountain lacks an official registration post, which allowed hikers to bypass warnings and enter via unofficial paths to view the crater.

For NPR News, I'm Nina Rao in Jakarta.