At least two people have died and a further 18 are missing after a huge mudslide buried homes on the flanks of a volcano in Ecuador on Friday.

The two died when their truck was engulfed by a torrent of mud and rocks which swept down the extinct El Altar volcano, 186km (116 miles) south of the capital Quito.

Another 30 people were taken to hospitals in nearby Riobamba, the capital of the province of Chimborazo.

A number of homes in Penipe and Guano, two small towns at the foot of El Altar, have been destroyed, and farms in an area known as La Candelaria have also been seriously affected.

Huge wave of water

According to local geologists, the mudslides were triggered by a glacier collapsing into a lake near the summit, causing a huge wave of water to spill over and cascade downwards.

One witness in Penipe described hearing a "huge roar that can still be heard," as the landslide threatened to engulf the town.

"The river swept away cows, still mooing," she said.

"It carried trees and huge rocks."

However, officials said they expected the death toll to remain relatively low due to few people living on the banks of the river.

El Altar ("The Altar") is 5,319m (17,021 ft) high and the fifth largest among a number of volcanoes dotted around Ecuador.