The Lie Tree first children's book to win Costa award for 14 years

A children's book has been named the Costa Book of the Year for the first time 14 years.

Frances Hardinge's supernatural tale The Lie Tree, set in the Victorian era, was hailed by judges as "a fantastic story".

It is the first children's book to win the coveted prize since Philip Pullman's The Amber Spyglass.

The Lie Tree follows teenager Faith, as she tries to uncover the details of her father's mysterious death.

The budding scientist finds a tree which, when fed with lies, bears fruit that acts as a gateway to understanding previously incomprehensible truths.

Her struggle for answers is set against the backdrop of a male-dominated Victorian society.

Despite not being the bookies' favourite, it saw off competition from debut novelist Andrew Michael Hurley's gothic horror story The Loney and esteemed author Kate Atkinson's A God In Ruins.

Judging panel chairman James Heneage said: "First and foremost, Frances Hardinge's The Lie Tree is a fantastic story."

Visibly surprised at hearing her seventh book was the winner, Frances Hardinge said she felt like she has "fallen through a hole to another dimension that seems implausibly idyllic, but I like it here and I am staying".

The 42-year-old author from London, previously worked as a technical author and a graphic designer while writing her first novel.

The Costa First Novel Award went to Andrew Michael Hurley for The Loney, which was the favourite to win the main prize, with prize winnings of £30,000.