El Salvador's highest volcano, Ilamatepec, has erupted, killing two people and forcing thousands to flee the area.
The ground shook as plumes of smoke and ash rose from the volcano, and burning rocks were hurled into the air.
Scientists said Ilamatepec had spat rocks as far as 1.5km (one mile) from its crater.
There have been reports of lava rocks the size of cars, and villagers fleeing from a flood of boiling mud and water.
Ilamatepec is El Savador's highest point at 2381 metres (7812 ft) above sea level.
Also known as the Santa Ana volcano, the volcano had lain dormant since 1904.
It lies about 65km (40miles) west of the capital, San Salvador.
Approximately 10,000 people live in the area surrounding the volcano.
On Friday, about 30 families were evacuated after columns of sulphuric smoke rose from the crater.
As it began to erupt, several thousand residents were evacuated and the government issued warnings to nearby villages.
A 4km (2.5-mile) radius around the volcano was declared a red alert area by the Salvadoran Interior Ministry, while a "yellow alert" was issued for neighbouring villages.
According to the AFP news agency, officials with the National Emergency Committee said 2,250 people had been evacuated from the danger zone.
There were also reports of at least seven injuries, and some locals have been treated for smoke inhalation.
The President of El Salvador, Antonio Saca, has warned that a second eruption cannot be ruled out.
But he called on El Salvadorans to remain calm, and described the eruption as one of "moderate magnitude".
He added that the country's civil protection forces had been deployed.
President Saca also warned people against going to watch the phenomenon of a volcano erupting.