Eleven climbers were found dead in Indonesia on Monday following the eruption of the Marapi volcano in West Sumatra, a rescue official said, as a search to find 12 more missing was temporarily halted over safety concerns.

Three survivors were found on Monday along with the bodies of the 11 climbers, among 75 in the area at the time of Sunday’s eruption, said Jodi Haryawan, spokesperson for the search and rescue team.

The 2,891 metre (9,485 ft) high volcano spewed ash as high as 3 km into the sky on Sunday.

Authorities raised the alert to the second-highest level and prohibited residents from going within 3 km of the crater.

Video footage showed a huge cloud of volcanic ash spread widely across the sky and cars and roads covered with ash.

A small eruption on Monday prompted the search to be suspended, Jodi said.

“It’s too dangerous if we continue searching now,” he said.

There were 49 climbers evacuated from the area earlier Monday and many were being treated for burns, he said.

Marapi is one of the most-active volcanoes on Sumatra island and its most deadly eruption was in April 1979, when 60 people died.

This year, it erupted between January and February and was spewing ash around 75 metres-1,000 metres from the peak.

Indonesia sits on the Pacific’s so-called “Ring of Fire” and has 127 active volcanoes, according to the volcanology agency.