A dozen workers on the set of new movie Olympus Has Fallen were taken to hospital after suffering heatstroke while building the movie's replica White House in the scorching Deep South.

The action film, starring Gerard Butler and Aaron Eckhart, centres on a terrorist attack on the home of the U.S. President, and producers ordered the construction of a full-size version of the property in Shreveport, Louisiana.

However, the location shoot was in trouble before cameras even started rolling, when onsite workers fell ill while erecting the set in soaring temperatures of up to 48 degrees Celsius (118 degrees Fahrenheit).

Butler tells British magazine Ok!, "We built the White House down in Louisiana over three months. It was tough - 12 of the builders had to be taken to hospital because the heat was so intense."