Reports from Argentina say at least 17 people have died as a result of freezing temperatures and heavy snow storms in Patagonia. A number died after inhaling lethal carbon monoxide fumes thought to have leaked from gas plants damaged by the bad weather.

Local authorities say they are trying to reach about 3,000 people who have been cut off; others are already being evacuated from their homes in some areas.

A spokesperson for the regional civil defence force said the weather was not improving and the situation was critical.

Temperatures have fallen below 25C over the past week. At least 10 people are also reported to have died in winter storms in southern Brazil.

From the newsroom of the BBC World Service