Fossils of teeth found in Dorset, Oxfordshire and Gloucestershire are believed to be the remains of the earliest relatives of birds, a group of dinosaurs called maniraptorans.

The fossils could belong to a dinosaur never seen before in Britain, according to Natural History Museum research conducted with help from artificial intelligence.

The findings include the oldest evidence in the world of the therizinosaur dinosaur, a large herbivore with long scissor-like claws which featured in the most recent Jurassic World film.

The Natural History Museum and Birkbeck College used machine learning to train computer models to identify which extinct animal the fossils were most likely to belong to.

The researchers gave the computers data about thousands of teeth from different dinosaur species and made 3D models of the fossils to find out which extinct creatures they were from.

Maniraptorans are thought to have walked the earth between 174 million and 164 million years ago during the Middle Jurassic era, but the new research suggests some of the dinosaurs could have existed almost 30 million years earlier.

Fossils from this time period are rare and little is known about the origins of these dinosaurs.

Simon Wills, a PhD student at the Natural History Museum, said: "Previous research had suggested that the maniraptorans were around in the Middle Jurassic, but the actual fossil evidence was patchy and disputed.

"Along with fossils found elsewhere, this research suggests the group had already achieved a global distribution by this time.

"The teeth we analysed include what are currently the only troodontid (a small bird-like dinosaur) and therizinosaur fossils ever recorded from the UK and are the oldest evidence of these dinosaurs anywhere in the world."

The Natural History Museum believes learning technology could be used more often to find out more about dinosaurs and their fossils.