The U.S. Pacific Tsunami Warning Center said there was a possibility of a local tsunami, within 100 or 200 miles of the epicenter, but they were not issuing an immediate warning for the broader region. The magnitude-7.5 quake, about 20 miles deep, was centered about 30 miles off the coastal town of Champerico. Nicaragua's disaster management agency said it had issued a local tsunami alert, but there were no immediate reports of a tsunami on the country's Pacific coast.
People fled buildings in Guatemala City, in Mexico City and in the capital of the Mexican state of Chiapas, across the border from Guatemala.
A reporter in San Marcos about 80 miles north of the epicenter, told local radio station Emisoras Unidas that houses had collapsed onto residents and smashed televisions and other appliances had been scattered into the streets of the town, which sits in a mountainous, mostly rural region.
The local fire department said on its Twitter account that a school had collapsed and eight injured people had been taken to a nearby hospital. Local radio reported widespread power outages and cuts in telephone service.
Guatemalan President Otto Perez Molina said in a radio interview that the country had been placed on its highest level of disaster alert and he asked people to evacuate tall buildings as an emergency measure. The country's minister of communications and infrastructure told Emisoras Unidas that landslides had cut off several highways in the west of the country, and it would take at least 24 hours to reestablish transport links to San Marcos.
A resident who identified herself as Mrs. Baglia told the radio station from the small town of San Pedro Sacatepequez, near San Marcos, that people had fled into the streets after being told of a tsunami alert.
"People are in distress and no one can calm down," she said.
A spokesman for El Salvador's Red Cross branch told The Associated Press that the quake had been felt throughout the country, sending people fleeing their homes in the capital, but there had been no immediate reports of injuries or serious damage. He said there had been no local tsunami warning issued. El Salvador's Civil Protection agency said officials were evacuating some coastal communities as a precautionary measure.
The mayor of Mexico City said no serious damage or injuries had been reported in the city, although many people had fled their offices and homes during the quake.