GUATEMALA CITY, GUATEMALA--A magnitude-7.4 earthquake that struck off the Pacific Coast of Guatemala has reportedly killed at least 15, after tremors shook buildings in nearby cities including Mexico City, Guatemala City and San Salvador.

The U.S. Pacific Tsunami Warning Center said there was a possibility of a local tsunami, but issued no warning for a larger region. The earthquake was about 20 miles deep and was centered 28 miles off the city of Champerico.

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.

The president says some of the deaths reported after the Wednesday quake have not yet been confirmed.

About 30 homes have collapsed and there are widespread reports of landslides and injuries in the town of San Marcos near the northwest border of Mexico, where most of the damage has been reported.

A reporter in the town of 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.

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, while Guatemala's emergency management agency also said on its Twitter account that it had received preliminary reports of one death from the quake.

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.

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.

Nicaragua's disaster management had issued a local tsunami alert, but there were no immediate reports of a tsunami on the country's Pacific coast.