After severe storms on the Indonesian island of Sumatra, the death toll has risen to at least 50. Civil protection said 27 people were still missing under huge masses of rubble, earth and rubble. “We will continue to search for them until we find them,” said the head of the authority.

Volcanic mud flows, so-called lahars, fell on the slope of the Marapi volcano in West Sumatra province on Saturday after heavy rain. Several districts were affected. Emergency services used heavy equipment to try to clear debris and reopen access to remote communities.

Lahars are extremely dangerous

At around 2,900 meters high, Marapi is one of Indonesia’s most active volcanoes with a long history of eruptions and lahars. Lahars – the word comes from Javanese – are considered particularly dangerous because they appear suddenly and rush rapidly down into the valley with their mix of mud, rock and rubble.

Indonesia, with its more than 17,000 islands, lies on the so-called Pacific Ring of Fire, the most geologically active zone on earth. Strong earthquakes and intense volcanic activity are not uncommon.