Hurricane Matthew, recorded as the most powerful Caribbean storm in a decade, has claimed the lives of over 300 people in Haiti, on Friday, a report said.

Initially categorised as a Category 4 storm, the hurricane downgraded to a Category 3 storm as it approached the US mainland,  heading towards the US state of Florida with sustained winds of 120mph (193km/h), BBC reported.

At 03:00 local time (07:00 GMT) Matthew was still off the Florida coast, centred about 37 miles (60km) east of Vero Beach and was moving north-west at about 14mph (22km/h), the National Hurricane Center said.

Hurricane Matthew has pounded the Bahamas after slicing through Haiti and Cuba.

Trees and power lines were reportedly down in the Bahamas but no fatalities were reported.

Most of the deaths in Haiti were in towns and fishing villages around the southern coast, with many killed by falling trees, flying debris and swollen rivers.

Many have lost their homes and are facing scarcity of food and water. The country is one of the world's poorest, with many residents living in flimsy housing in flood-prone areas.

Meanwhile in the US, evacuation orders have been issued for areas covering some three million inhabitants.

In Florida, heavy rains and high winds lashed the Miami area overnight. Some 200,000 homes and businesses have been left without power in the state already.

Sustained winds could reach 130mph, with gusts of up to 160mph, with rainfall of up to 15in (38cm).