Mao Tse-Tung's "Little Red Book" is the closest thing to a bible that Marxist-Leninist, materialist and atheist Chinese society can have.

By some estimates, five billion copies of The Thoughts of Chairman Mao were published during its heyday, the Cultural Revolution, that violent period of ideological fervour in the 1960s and 1970s. But questions have now been raised about whether the Great Helmsman actually wrote it himself, or got a ghost writer to do it for him.

The book of quotations from communist China's founding father Chairman Mao Tse-tung, was a must-have in the days when Red Guards roamed the streets looking for any signs of ideological wavering. It was also the revolutionary tome of choice for every western Marxist-Leninist hipster on university campuses. Pithy and strident aphorisms such as, "it is the duty of the cadres and the Party to serve the people. Without the people's interests constantly at heart, their work is useless," helped to establish a cult of personality around Mao Tse-tung so powerful that the current leadership of China is still trying to shake it off.

But lately there has been a flurry of online rumours that some of Mao's writings were not written by Mao himself, but by his secretary Hu Qiaomu and others. Some of those who grew up in the Mao era find it impossible to believe that their idol might not be the true author of the writings that were the doctrine of their upbringing.

"I can't believe it. No, no, no," said one 60-year-old man. "If it is true, then I will be really disappointed. Everyone in my generation loves him, he is like the whole of our soul. This must be mistake, really, he is just too important."

But younger people are more prepared to accept that the musing may not actually have been written by the chairman: "I'm sure it was Mao's ideas originally, but as to the actual writing and putting it together, who knows? Maybe someone helped him sort out his materials, record his speeches, write drafts, that kind of thing," said a 29-year-old woman.

It is rumoured that two reports detailing the ghostwriters' activities were filed with the Central Committee in 1993 and in 1995. So vocal have the sceptics become that a website, which is affiliated to the People's Daily newspaper, ran a statement denying the rumours, quoting a spokesman from China's ideological heavyweights – the Party Literature Research Centre, the Party History Research Centre and the Party School of the Central Committee of Communist Party of China.

The spokesman said Mr Hu had spoken on many occasions of how Mao would help him edit the articles and how he had learnt his poetic style from the Chairman.

Mao is a revered figure in China, and his face gazes impassively at Tiananmen Square from its vantage point above the gate of the Forbidden City.