At least five killed by tornadoes in central US

At least five people have been killed after tornadoes ripped through the central US, destroying buildings and a fuel station that was sheltering dozens of people.

Severe storms formed over Texas and Oklahoma on Saturday night, with Cooke County north of Dallas among the hardest-hit areas.

Local sheriff Ray Sappington said the death toll from the storms was expected to rise.

"We're still in search and rescue mode right now. I hope we can still find survivors," he told local media.

Footage broadcast by local media showed a fuel station almost completely destroyed, with twisted metal littered over damaged vehicles.

The storms overturned lorries and shut down a highway near Dallas.

The National Weather Service issued tornado warnings for parts of Texas and Oklahoma on Saturday, an area already in the grip of extreme heat.

The Central Plains of the United States are nicknamed Tornado Alley. Their location and climate mean they are highly prone to some of the most destructive tornadoes on the planet.

May is typically the most active month of the year for severe tornadoes.