At least 52 people have been killed and hundreds remain missing after a powerful earthquake struck off the Pacific coast of Guatemala, where a tsunami warning has now been issued.

About 125,000 people were without power as a result of the quake.

The 7.4-magnitude earthquake centered about 160km southwest of Guatemala City. It is the strongest to hit the country since a deadly 1976 quake that killed 23,000.

The death toll is feared to rise as survivors report widespread landslides and people trapped under the rubble.

The quake was so powerful that it made crossways from Guatemala City to neighboring Mexico City. The US Pacific Tsunami Warning Center said there was a possibility of a local tsunami, within 320km of the epicenter.

Local radio reports widespread power outages and cuts in telephone service.

The mountain village of San Marcos, 130km from the epicenter, has suffered extensive damage with some 30 homes destroyed. More than 2,000 soldiers have been sent to help with the relief effort.

Guatemalan President Otto Perez Molina has asked people not to travel on motorways, as several highways in the west of the country have been cut off by landslides.