Novelist Sue Townsend, best known as the author of the Adrian Mole series of books, has died, according to a family friend.

The 68-year-old writer died yesterday after a short illness.

Townsend, who was left blind after suffering from diabetes for many years, achieved worldwide success after the publication of her best-known work, The Secret Diary Of Adrian Mole aged 13 3/4 , in 1982.

Fellow Leicester author Bali Rai said that Townsend’s family had told him of her death.

Mr Rai told The Sun he had spoken with Townsend's son Danny, who said she died at about 9pm yesterday but would not confirm she had died from a stroke.

Mr Rai said on Twitter: “Just been informed by her family that my hero, SueTownsends has passed away. Utterly shocked and saddened. An amazing woman is gone.”

He added: “...she was one of our own, and a unique voice in British Literature. She will be missed... In an age of plastic idiots, she was a true role model.”

Stephen Mangan, who played Adrian Mole in a 2001 television adaptation, tweeted his condolences, saying: "Greatly upset to hear that Sue Townsend has died. One of the warmest, funniest and wisest people I ever met."

Townsend was born in Leicester in 1946, and set her most famous work in her home city.

She left school at the age of 15, married at 18 and by 23 was a single parent with three children, a biography from her publisher, Penguin said.

After writing in secret for 20 years while working as a factory worker, shop assistant and youth worker, she eventually joined a writers’ group at the Phoenix Theatre in Leicester when she was in her 30s.

At 35 she won the Thames Playwright Award for her play Womberang and a year later published the first in her series about Adrian Mole, which she had begun writing in 1975 while living in Leicester's Saffron Lane estate.

The Secret Diary Of Adrian Mole aged 13 3/4 was published in 1982, followed by The Growing Pains Of Adrian Mole in 1984.

The two books made her the best-selling novelist of the 1980s, and were followed by six others in the Mole series, including The True Confessions Of Adrian Albert Mole and most recently Adrian Mole: The Prostrate Years, in 2009 .

Much of Townsend’s life was blighted by illness.

She had a heart attack in her 30s and suffered from diabetes for many years, leaving her registered blind in 2001 and forced to resort to dictating her work.

In 2009, she had a kidney transplant, also a complication of her diabetes, which was donated by her son, Sean.

Speaking in 2012 she said: ”He felt it more than I did. I’m used to having operations but he’d never been in hospital before. There was never any hesitation, though.

“I was thrilled he was going to give me his kidney, but also scared for him and truly appreciated it.”

In recent years she was left wheelchair-bound, with neuropathy in her limbs.

Townsend also wrote a number of other novels, including The Queen And I , as well as further plays and two non-fiction books.

Several of her books were adapted for the stage, while the Mole series were adapted for radio, television and theatre.

In 2001, she wrote The Public Confessions Of A Middle-Aged Woman aged 55 3/4 , a collection of monthly columns written for Sainsbury's magazine from 1993- 2001.

Townsend was awarded an honorary Masters of Arts from Leicester University and in 2008 was made a Distinguished Honorary Fellow, the highest award the university can give.

She was also an Honorary Doctor of Letters at Loughborough University and a Fellow of the Royal Society of Literature.

Townsend was given the Honorary Freedom of Leicester in 2009.

She said at the time: ”I have been a citizen of Leicester for over 62 years, most of my family and friends live here, so I was delighted when I was nominated to receive the freedom of the city.”

She leaves behind her husband, Colin Broadway, and four children.

PA