Palaeontologists say they’ve found fossils from a previously undiscovered species of dinosaur hidden in slabs of Utah sandstone that were so hard explosives had to be used to free the remains.

The bones found at Dinosaur National Monument are a type of sauropod, which were long-necked plant-eaters said to be the largest animal ever to roam land.

Details of the find were made public on Tuesday and are being published in a peer-reviewed science journal.

The new species is called Abydosaurus mcintoshi.

Monument palaeontologist Dan Chure says the fossils offer fresh insight into lives of dinosaurs some 105 million years ago.

Dinosaur National Monument straddles the Utah-Colorado border.

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