Drawings by author Roald Dahl to be sold at auction

The drawings will be sold at auction alongside a collection of other items

Pictures drawn for a book about the life of children's author Roald Dahl are going on auction after being found in an envelope.

The famous author drew the images himself using a black ballpoint pen for Boy, which was published in 1984.

The book is the only which Dahl produced illustrations for during his long career.

The sketches, which are expected to be sold on Wednesday, are part of a collection estimated to sell for between £20,000 and £30,000.

Roald Dahl wrote lots of famous stories but only drew sketches for his memoir, Boy

In his book, Dahl describes some of the things he got up to as a child, including playing a prank with his friends on the local sweetshop owner Mrs Pratchett by putting a dead mouse in a gobstopper jar.

Dahl drew a mouse lying on top of the sweets with its legs in the air to illustrate the naughty act.

The drawings were found in an envelope belonging to Ian Craig, who ended up creating the final illustrations for the author's memoir.

He stepped in as Dahl's usual illustrator, Quentin Blake, was away on holiday at the time.

"The publication of Boy was on a very tight publication schedule," said Ian Craig's widow Kate.

"As Quentin Blake was away on holiday, Ian asked Dahl if he could help with the illustrations.

"Dahl ended up producing a variety of sketches which Ian used as inspiration for his own drawings."