Miami, Oct 11: At least two people were killed as Hurricane Michael, one of the most powerful storms ever to hit the continental the US, slammed into the state of Florida, unleashing a trail of destruction by flooding beach towns, peeling off roofs and snapping trees before advancing to the Carolinas.

Two people, including a child, were killed by falling debris, the US media reported on Thursday. Hundreds of thousands of homes and businesses were left without electricity in Florida, Alabama and Georgia.

Michael made landfall on Wednesday around 2 p.m. near Mexico Beach, Florida, dashing homes into pieces, swallowing marinas and leaving piles of rubble where shopping centres once stood, CNN said.

It was the strongest to hit the continental US since Hurricane Andrew in 1992.

"Hurricane Michael is the worst storm that the Florida Panhandle has ever seen," said Governor Rick Scott of Florida, where 375,000 people were ordered evacuated.

Now, having weakened to a tropical storm, Michael was on its way to the Carolinas. However, the National Hurricane Centre (NHC) said that winds picked up at certain points along the Georgia and South Carolina coast.

Large parts of Georgia, the Carolinas and southeastern Virginia could still see deadly flash floods on Thursday and remain under a tropical storm warning, it said.

Storm-surge warnings were in place between Panama City Beach and Keaton Beach in Florida, and between Ocracoke Inlet and Duck in North Carolina.

According to officials, one person was killed on Wednesday after a tree fell on a house near Greensboro, Florida. The second death was reported in Georgia's Seminole County early Thursday, apparently caused by debris crashing through a mobile home and killing a child inside, the Washington Post reported.

Travis Brooks, Director of Seminole County's emergency management agency, told ABC News there was "complete and total devastation".

The entire county was "pitch black" and there were no clear roads, he said.

The hurricane earlier reportedly killed 13 people as it passed through Central America: six in Honduras, four in Nicaragua and three in El Salvador.

Hurricane Michael kills 2 in US, heads to Carolinas