The authorities have finally rumbled the nation’s most famous illegal immigrant.

At a time of heightened sensitivity to mass immigration, the refugee background of Paddington Bear has persuaded Michael Bond to write his first novel about him for 29 years.

In a surprisingly political opening chapter to Paddington Here and Now police interrogate the duffelcoat-wearing stowaway from darkest Peru about his residency status and right to remain in England.

The novel is to be published next June to mark the 50th anniversary of the debut of the character in A Bear Called Paddington, in which the Brown family adopted a homeless bear who they spotted amid a pile of mailbags on a platform at Paddington station. The new book is again set around their home at 32 Windsor Gardens, Notting Hill, and revisits the stalls in Portobello Road where Paddington has enjoyed sharing cocoa and buns with another immigrant: Mr Gruber, the Hungarian antiques dealer.

Further plot details are guarded as fiercely as the marmalade sandwiches that Paddington keeps under his hat “for emergencies”. Presumably, however, he fixes his police interviewers with a particularly hard stare because he survives the brush with the law to continue wreaking his familiar brand of mild havoc around London.

The Paddington books have sold more than 30 million copies and been translated into 30 languages. The appeal of the accident-prone bear remains undiminished after half a century. When he branched out from marmalade in a recent television advertisement for Marmite, it made headlines around the world.

Mr Bond was working as a BBC cameraman when a bear he bought in Selfridges for his wife on Christmas Eve inspired him to write the original novel. Now 83, he has continued to write occasional short stories about his best-loved creation since the publication of Paddington Takes the Test, the last novel, in 1979.

However he was reluctant to add to the 11 books unless he had a strong, contemporary storyline, according to Sue Buswell, who bought the rights to the new book for HarperCollins Children’s Books.

She told The Times: “We started talking about it several years ago and he had a twinkle in his eye. This novel chimes with where we are now rather than 1950s Britain. It’s about the nature of what makes a place your home, where you belong. These are important questions and they are less clear-cut than they were when Michael wrote the first book.”

In the book a misunderstanding leads to Paddington being arrested and taken to his local police station where he faces questions about his immigration status. Fans of the bear will know that his Aunt Lucy arranged for him to stow away on a ship’s lifeboat from Peru after she went to live in the Home for Retired Bears in Lima. Therefore, he has no papers proving his identity, Ms Buswell said, “although it all works out as it always does with Paddington”.

“I think [writing it] made Michael reflect on the people who have come to live here and how their lives have been built in a new country. There’s a lot to say about that and it’s very moving. It feels bang up to date, although Paddington himself is unchanged.”

Mr Bond told The Bookseller: “Basically, Paddington Bear is a refugee and, when I wrote the first book, one of the things I gave him was a label around his neck to say, ‘Please look after me’. Paddington comes from a different country and there are very few people around him who understand what that feels like. He needs to decide where, for him, is home.

“One of the very nice things about chronicling Paddington’s adventures is that although the world has changed considerably over the past 30 years, he remains exactly the same: eternally optimistic and ever open to what life has to offer. It makes writing the stories a pleasure.”

Paddington Here and Now will have a cover illustration by Peggy Fortnum, 85, who did the first drawings of Paddington. The 50th anniversary will also be marked by reissues of the novels and picture books and a new title, My Book of Marmalade. The following year, a computer-animated Paddington will be the subject of a Hollywood film from David Heyman, the producer of the Harry Potter films, who agrees with Mr Bond about the bear’s relevance to a modern audience. Earlier this year he explained the appeal of a universal story of “an immigrant arriving in London and trying to find a home and a family”.

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