Hundreds of rescuers are sifting debris of wrecked towns for survivors of Wednesday's earthquake in Guatemala.
The 7.4-magnitude tremor, the most powerful to hit Guatemala since 1976, left at least 52 people dead, many more injured and thousands without power.
President Otto Perez Molina told the BBC that 22 people were still missing and as many as 10,000 houses may have been rendered uninhabitable.
Most of the damage was in San Marcos region, near the border with Mexico.
The president, who visited the affected area on Wednesday, declared three days of mourning.
He told BBC Mundo that rescuers were continuing to search through the rubble.
"We have identified the places where [survivors] could be, and rescue units are working there," he said.
The mountainous town of San Marcos and the surrounding area was hit particularly hard, with 40 people confirmed dead.
Many residents spent the night outside, huddled under blankets and afraid to go back into their homes.
The only building left with electricity in the area was the hospital, which was packed with the injured and their families.
In San Cristobal Cucho, a village 5km (3 miles) from San Marcos, 10 members of the same family were killed when their house collapsed.
"The whole village is in mourning because an entire family was taken by God's nature. What can we do," said local mayor Pedro Cardona.
The other fatalities were in the neighbouring region of Quetzaltenango.
About 2,000 soldiers joined hundreds of rescuers in a bid to find any possible survivors on Thursday.
"We started rescue work very early," said Julio Cesar Fuentes of the municipal fire department.
"The objective is our hope to find people who were buried."
Late on Wednesday, the energy ministry said about 73,000 people were left without electricity.
Roads had been deluged by landslides and most regions of the country reported some damage as a result of the quake.
Powerful aftershocks continued to hit the area throughout the night.
The original tremor hit 23km off Guatemala's Pacific coast on Wednesday at about 10:35 local time (16:35 GMT).
The shudders sent people fleeing from buildings in El Salvador to the south, and as far north as Mexico City.
Officials said it was the worst earthquake to strike Guatemala since 1976, when a 7.5-magnitude tremor caused the deaths of about 25,000 people.
Panama, El Salvador and Honduras have offered their help with the rescue operation.