Around 3,000 people have been evacuated from their homes after Nicaragua's tallest volcano erupted, billowing smoke and ash almost three miles into the sky.
Residents reported hearing three powerful explosions in the San Cristobal volcano, located 83 miles (135km) northwest of the capital Managua.
Ash has fallen on the towns of El Viejo, El Chonco, Villa 15 de Julio and Rancheria, according to the Nicaraguan Institute of Territorial Studies (INETER), which monitors volcanic activity.
There are fears that winds could push the fumes from the eruption towards those villages, which are perched on the slopes of the volcano.
William Gonzalez, the director of the national disaster prevention and mitigation agency, said authorities had ordered the evacuation of some 3,000 people.
Civil defence personnel said 350 troops and 50 trucks were on emergency standby, while INETER said it expected "more gas emissions and sporadic explosions".
Javier Mejia, director of Nicaragua's geological institute, said monitoring instruments showed "strong activity" in the volcano.
"We do not rule out anything, but call for calm," he added.
The 5,740ft (1,740 metre) San Cristobal is one of the country's most active volcanoes.
Nicaragua has been on alert since a strong earthquake shook neighbouring Costa Rica on Wednesday triggering a swarm of minor tremors in the area around Managua the following day.