At least 52 people have been killed, 22 missing and 1.2 million others affected by the 7.4-magnitude earthquake which hit the country's Pacific coast Wednesday, said Guatemalan President Otto Perez Molina.

The temblor also jolted Mexico and El Salvador. "The number of people (dead) is rising, officially we have 52 dead, 22 missing, and rescue workers are searching the rubble," Xinhua quoted the president as saying in a press conference Thursday. He also announced three days of national mourning for the victims.