A series of powerful storms and tornadoes have killed at least 28 people in the US states of Indiana, Kentucky and Ohio, officials say.

Local police confirmed that at least 13 people died as tornadoes swept across three counties in Indiana.

Twelve more died in Kentucky, with two fatalities in Ohio. Earlier, tornadoes hit Alabama, killing one person.

"We are no match for Mother Nature at her worst," said Indiana Governor Mitch Daniels.

There are fears the death toll may rise as the scale of the devastation and the breadth of the storms made immediate assessments of the destruction difficult.

The storms - stretched across a vast part of the US Midwest - came days after another system killed 13 people.

The first deaths on Friday were reported in Indiana, where the small town of Henryville was badly damaged.

Reports of extreme damage includeda roof torn off a high school.

An official from Clark County sheriff's department described the nearby town of Marysville, Indiana - located close to Henryville - as "completely gone".

Jenn Helvering, 24, told the BBC she saw a storm cell cross the highway as she drove towards Henryville. She then came across wreckage, including an overturned tractor-trailer, alongside the road near the town.

Ms Helvering, who posteda series of imagesonline said she saw "what seemed to be a funnel", when driving between two storm cells.

"The weather was terrible. I suddenly saw a tornado coming towards me, I could see it swirling, then I saw one behind me. I was stuck in between two tornadoes - my dad directed me while I was driving between the two tornadoes. It was truly terrifying."

'Take cover!'

In Salem, Indiana, a toddler was found injured in a field after tornadoes passed through, reports said before being taken to a children's hospital, where she was later identified.

A family of four were found dead in Washington County, Indiana, Sheriff Claude Combs told the Louisville Courier-Journal.

Meanwhile, in Henryville, authorities found a man dead inside his vehicle. It was the first confirmed death in Clark County.

"We've got total devastation in the north-central part of the county [and] widespread damage from the west to the east," Clark County Sheriff Clark Adam told CNN.

Neighbouring Marysville was totally destroyed.

"Marysville is completely gone,'' said Chuck Adams of Clark County Sheriff's Department.

As Friday's storms grew in intensity, the National Weather Serviceissued severe tornado warningsfor a host of states.

By 19:30 EST (00:30 GMT on Saturday) tornado warnings were in effect across swathes of Alabama, Kentucky, Tennessee and Indiana, with parts of West Virginia and Florida also under advisory.

In a strongly worded warning, the NWS said residents in the path of the Indiana storm were facing an "extremely dangerous and life threatening situation".

"If you are in the path of this tornado... take cover immediately!" the NWS said.

Additional tornadoes were reported near Mumfordville, Kentucky and Memphis, Indiana, as well in southern Ohio.

Local TV broadcaster WHAS in Kentucky showed a storm-tracking team driving through Mumfordville, speeding away from a potential tornado as golf-ball sized hailstones fell from the sky.

As the evening progressed more details of the scale of destruction began to emerge, with officials in Kentucky and Ohio confirmed fatalities there.

Earlier this week, 13 people died after twisters swept through Missouri, Kansas, Illinois and Tennessee.

Houses flattened

On Friday morning five people were taken to hospital and 11 houses were flattened in the town of Athens, Alabama by an apparent tornado in the Huntsville area.

More than 20 school networks in Alabama closed early on Friday because of the weather warning.

Image caption Jenn Helvering posted images of damage on social media site Instagram

Local media reported that about 9,000 people lost power in the area around Huntsville.

A possible twister also hit a maximum security jail near Huntsville, although officials said inmates remained secure.

The severe weather warning was to remain in place until about midnight on Friday.

The town of Harrisburg, Illinois, was particularly badly damaged on Wednesday by the storm system.

Six residents died there, while three deaths were reported in Missouri, three in Tennessee and another in Kansas.