Johan Ordonez / AFP - Getty Images

A girls looks inside a house damaged by an earthquake on the eve in San Marcos, 260 km from Guatemala City, on Thursday, Nov. 8, 2012, a day after a 7.4-magnitude hit off the Pacific coast of the country.

Updated 5:25 p.m. ET

SAN MARCOS, Guatemala — Guatemalans fearing aftershocks huddled in the dark and frigid streets of this mountain town wrapped in blankets early Thursday, while others crowded inside its hospital, the only building left with electricity after a powerful earthquake killed at least 52 people and left dozens more missing.

Crews worked through the night in San Marcos, searching rubble for survivors and more dead following the magnitude 7.4 quake that struck Wednesday near Guatemala's border with Mexico.

Local Red Cross chief Carlos Enrique Alvarado told Reuters 75 homes were destroyed in San Marcos alone and authorities said damage to the prison forced them to transfer 101 inmates to another jail. Officials told The Associated Press that most of 100 missing were from San Marcos.

The quake, which was 20 miles deep, was centered 15 miles off the coastal town of Champerico and 100 miles southwest of Guatemala City. It was the strongest earthquake to hit Guatemala since a 1976 temblor that killed 23,000.

PhotoBlog: Desperate search continues for quake survivors in Guatemala

In the town of San Cristobal Cochu, firefighters picked at a collapsed house trying to dig out 10 members of one family, including a 4-year-old child, who were buried, fire department spokesman Ovidio Perez told the radio station Emisoras Unidas.

Volunteers carrying boxes of medical supplies began arriving in the area in western Guatemalan late Wednesday.

Johan Ordonez / AFP - Getty Images

A firefighter looks bodies of people who died in the earthquake that hit San Marcos, Guatemala, on Wednesday.

Eblin Cifuentes, a 26-year-old law student, and a group of his classmates already were collecting medical supplies as part of a school drive to provide aid for the only hospital in San Marcos, a poor, mainly indigenous mountain area of subsistence farms. When the quake hit, the group decided to bring everything they had collected.

"Thank God nothing happened to us and that's why we have to help out," Cifuentes told the AP.

Deadly quake rocks Guatemala, is felt in Mexico City

Rescue workers in bright yellow helmets worked through the night pulling bodies from the rubble-strewn streets of San Pedro Sacatepequez, San Marcos, as dazed locals looked on, taking stock of the damage.

"Thank God we're alive," resident Arnulfo Portillo told Reuters. "To be honest, there's quite a few families who have been hit badly, but we're a tight-knight community and we'll come out on top."

Hundreds of frightened townspeople stayed in the open, refusing to go back inside after more than five strong aftershocks shook the area.

President Otto Perez Molina said that 40 people died in the state of San Marcos and eight more were killed in the neighboring state of Quetzaltenango.

PhotoBlog: Wrecked buildings, crushed cars and rescues

Mom: 'He's not dead. Get him out'
Hundreds of people crammed into the hallways of San Marcos' small hospital after the quake seeking help for injured family members. Some complained they were not getting care quickly enough.

Ingrid Lopez, who bought in a 72-year-old aunt whose legs were crushed by a falling wall, said she had waited hours for an X-ray. "We ask the president to improve conditions at the hospital," she told the AP. "There isn't enough staff."

More than 300 firefighters, policemen and civilians dug desperately at a half-ton mound of sand at a quarry trying to rescue seven people believed buried alive. Among those under the sand was a 6-year-old boy who had accompanied his grandfather to work.

"I want to see Giovanni! I want to see Giovanni!" the boy's mother, 42-year-old Francisca Ramirez, frantically cried. "He's not dead. Get him out."

By Wednesday night, firefighters had dug out two bodies from the quarry, including Giovanni.

President Perez flew to San Marcos to view the damage in this lush mountainous region of 50,000 indigenous farmers and ranchers, many belonging to the Mam ethnic group.

"One thing is to hear about what happened and another thing entirely is to see it," he told The Associated Press. "As a Guatemalan I feel sad ... to see mothers crying for their lost children."

Perez said the government would pay for the funerals of all victims in the impoverished region.

Girl died while playing
Efrain Ramos helped load a tiny casket carrying the body of his 6-year-old niece from San Marcos' morgue to a waiting pickup truck.

"The little girl died when a wall fell over her," a shocked Ramos told a reporter. He said the girl was playing in her room when the quake hit.

Sobbing uncontrollably, the girl's mother hugged the coffin wrapped with white lace and tulle.

The quake caused terror over an unusually wide area, with damage reported in all but one of Guatemala's 22 states and shaking felt as far away as Mexico City, 600 miles to the northwest.

In Guatemala City, 100 miles from the quake's epicenter, the streets filled with office workers forced to evacuate buildings, although most soon returned to work.

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