At least 192 people are missing and 75 are dead as a result of the explosion of the Fuego volcano in Guatemala on Sunday, according to authorities.
The villages on the hillsides were buried in volcanic ash and mud.
The rescue work on Tuesday was interrupted when a new eruption sent hot gas and molten rock running down the south side of the volcano.
More than 1.7 million people have been affected by the eruption on Sunday, with more than 3,000 evacuated.
The blast on Tuesday took many by surprise after volcanologists said the eruption, which had sent ashes up to 10 km (33,000 feet) to the sky on Sunday, had ended in the near future.
Eddy Sanchez, the head of Guatemala’s National Institute of Seismology, had predicted “no imminent eruption over the next few days”.
Why were so many people killed in the initial eruption?
Nearly 200 people remain missing, the AFP news agency said, citing Guatemala’s Disaster Relief Agency.
No evacuation alert was issued before the volcano erupted on Sunday, said the agency’s chief, Sergio Cabañas.
He added that local residents had received training in emergency procedures but could not implement them because the initial volcanic activity occurred too quickly.
The explosion on Sunday generated pyroclastic flows (very hot gas mixtures and rapidly moving volcanic material) that descended the hillsides, engulfing communities such as El Rodeo and San Miguel Los Lotes.
Volcanologist Dr. Janine Krippner told the BBC that people should not underestimate the risk of pyroclastic flows and volcanic mudflows, known as lahars.
“Fuego is a very active volcano. It has deposited quite a bit of loose volcanic material and it is also in a rain-heavy area, so when heavy rains hit the volcano that is going to be washing the deposits away into these mudflows which carry a lot of debris and rock.
“They are extremely dangerous and deadly as well.”