BOGOTA -- The latest eruption by Colombia's Nevado del Huila volcano caused avalanches that destroyed bridges and left vast farm regions, villages and Indian settlements isolated, but authorities have received no reports of casualties.

The volcano, which stands 5,634 meters (18,472 feet) above sea level and is located 500 kilometers (310 miles) southwest of Bogota, erupted at 9:45 p.m. Thursday (0245 GMT Friday), according to the Colombian Institute of Geology and Mining.

President Alvaro Uribe flew Friday over the area affected by avalanches after the volcano erupted and said that in principle there were no victims thanks to the mechanisms of prevention and evacuation employed by the inhabitants in high-risk regions.

"May God let there be no bad news about the people living there, and may we have no reports of a more serious situation," the president said to reporters at one stop on his flight over the disaster area.

Uribe said that it was possible that there would be victims, since according to the inhabitants of the area, some villages could have been wiped out or left incommunicado, but he added that technical authorities say that "everything was working and operating on time" with regard to disaster-prevention plans.

A June 1994 avalanche on Nevado del Huila killed more than 1,000 people and caused massive crop losses.

Avalanches, landslides and mudslides in the last few hours affected settled riverside areas in Cauca and Huila provinces.

But scientists at the geology institute said that "volcanic activity has greatly diminished, although there are still small tremors," and added that "for now we continue to observe the situation and maintain a red alert." EFE