Hurricane Michael kills 17 in US

Miami: The death toll from hurricane Michael, one of the most powerful storms to make landfall in the US mainland, has increased to 17, with coastal Florida cities damaged beyond recognition, and homes, businesses and agriculture torn or swamped from Georgia to Virginia.

More than 1 million people were left without electricity, and emergency officials have no access to many towns, CNN reported on Saturday.

The toll is also expected to climb as search and rescue efforts continue.

"I expect the fatality count to rise as we get through the debris," Federal Emergency Management Agency Administrator Brock Long said on Friday.

The 17 victims comprised eight from Florida, five in Virginia, three in North Carolina and a child in Georgia.

Michael made landfall in the Florida Panhandle on Wednesday as a Category 4 hurricane -- the strongest on record to hit the area -- and charged north through Georgia and into the Carolinas and Virginia, wreaking havoc and causing emergencies.

Senator Bill Nelson called the devastation "the worst destruction that the Panhandle has seen for however long that I've been living. It's akin to Hurricane Andrew in 1992 where everything was levelled".

Aerial footage shows coastal cities in the Panhandle, like Mexico Beach, wiped out, CNN said.

A psychiatric hospital in Florida is isolated after downed trees blocked roads around Chattahoochee, and a tree caused a water line to break.

The facility is running on power generators, and helicopters have delivered food and water, the state's Department of Children and Families said.