A volcano eruption in southwest Colombia sent smoke and ash into the sky Thursday and raised concerns for the safety of neighboring villagers, officials said.
Police and emergency officials were placed on high alert after the 4,276-meter Galeras volcano became active at dawn Thursday and dumped heaps of ash on the city of Pasto, 20 kilometers away.
"It was a brief eruption of ash for 30 minutes that was not preceded by a temblor inside the volcano," said Marta Lucia Calvache of Colombia's Volcanology Institute. "But there is still a thin plume of ash leaving the crater, and we can't rule out the possibility of further eruptions."
The government this month ordered the preventive evacuation of thousands of people living in the shadow of the volcano amid signs of an imminent eruption. But many farmers are believed to have defied the order and stayed behind, fearful of losing their livelihoods by leaving their crops unattended.
Calvache urged any families who remain in a wide area surrounding the volcano to leave immediately and seek medical treatment if they have trouble breathing.
Schools and many offices in Pasto were closed for the day.
The Galeras has a long history of activity, fraying nerves in Pasto. More than 100 minor tremors were felt in the city during the volcano's last major eruption, in April 2002, though no damage or injury was reported.
A 1993 eruption killed nine people, including five scientists from around the globe who had descended into the crater to sample gases at the moment it blew, the AP reports.