At least 16 people have been killed by tropical storm Agatha and the deadly landslides it triggered in Central American countries, while several thousands were forced for evacuation.

Two adults and two children were killed when a boulder dislodged by the rains crushed their home in Alomolonga, in Quetzaltenango province, about 200 km west of the capital, emergency officials said.

Eight people were killed by mudslides in Guatemala City and the town of Santa Catarina Pinula.

The country's death toll is expected to climb up as an additional 11 people were reported missing and 3,000 were evacuated as Agatha, the first storm of the current Pacific hurricane season, picked up momentum and heavy rains flooded three rivers in the west part of the country.

Guatemala has declared a state of emergency as the storm moved closer with a maximum sustained wind speed of 75 km per hour. President Alvaro Colom said the government would provide 85 million U.S. dollars in loan for relief to storm victims and those affected by the ongoing eruption of volcano Pacaya.

In El Salvador, the storm triggered some 140 landslides across the country, killing at least three people. The country's President Mauricio Funes has declared a state of emergency.

In Honduras, one person was killed by a collapsed wall in the town of Santa Ana, near the capital city of Tegucigalpa. Some 1,500 people were evacuated, according to the authorities.

Agatha has gradually weakened as it moved inland early Sunday. But Eddy Sanchez, head of the Meteorological and Seismology Institute, said the rains would continue to fall through Tuesday.