Nicaragua's San Cristobal volcano shot tons of ash into the sky after forcing evacuations of nearby towns, officials said.
A column of smoke and ash rose from the cone of the volcano, Nicaragua's tallest at 1,745 meters (5,725 feet), in the northeast, where rumbling a day earlier prompted nearby hamlets to be ordered evacuated.
But volcanic activity did not appear to have worsened, according to the Nicaraguan Institute of Territorial Studies, or INETER. Still, the volcano was shooting as much as 3,221 tons of ash into the sky, compared to an average day of 550-700 tons, it said.
"The high sulfur emissions, eight times higher than normal mean that the volcano has its own internal activity and that there could be more explosions," said INETER geophysics chief Angelica Munoz.
San Cristobal, located 135 kilometers northwest of the capital Managua, is among seven active volcanoes in the Central American nation. It is believed to have erupted for the first time in 1685.
Explore further: Ocean could hold the key to predicting recurring extreme winters