People in Florida have been told to prepare for the largest evacuation effort for years as a new hurricane heads for the Gulf Coast, which is still reeling from another historic storm.

Hurricane Milton, off the Mexican coast, could threaten lives when it reaches the state's west coast in the middle of the week, the National Hurricane Centre (NHC) says.

It comes just 10 days after Storm Helene - the deadliest mainland storm since Katrina in 2005 - tore through the US south-east, killing at least 225 people.

Hundreds of others are still missing.

At least 14 of those deaths were in Florida, where 51 of 67 counties are now under emergency warnings as Milton approaches.