At least four people have died in a large forest fire that has destroyed at least 150 homes, forced thousands to evacuate and covered the Chilean city of Valparaiso in smoke.

"We have four people dead - three men and a woman," Rodrigo Penailillo, Chile's interior minister, told Radio Cooperativa on Sunday, giving a provisional death toll from the fire, which is being battled by hundreds of firefighters.

Michelle Bachelet, the Chilean president, has declared the port city a catastrophe zone, which puts the armed forces in charge of maintaining order and evacuating thousands of people affected by the smoke and flames.

Valparaiso Mayor Jorge Castro told Chile's National Television that people were having difficulty breathing through the smoke. Refuges have been set up for those forced to flee the blaze.

Castro said on Saturday night that "Valparaiso is without electricity at the moment and this means the flame column is creating a Dante-esque panorama and is advancing in an apparently uncontrollable manner''.

The National Office of Emergency also decreed a red alert for the La Polvora area, where around 150 hectares of grassland, bushes and eucalyptus have been burned.

The cause of the fire, which began in woodland near the city late on Saturday, is being investigated.

Source: AP