Michael Schumacher's medical files have been stolen and are apparently being offered for sale online.

It was announced last week that the seven-time Formula 1 world champion was no longer in a coma and had been transferred to a hospital in Lausanne, Switzerland.

However, that promising news has been dampened by the revelation that his medical notes had been thieved and are supposedly available to the highest internet bidder.

Schumacher's camp and family are investigating the authenticity of the documentation and have warned that they will press criminal charges against the perpetrator if private information is published.

A statement from Schumacher's manager Sabine Kehm read: "For several days stolen documents and data are being offered for sale. The offeror claims them to be the medical file of Michael Schumacher.

"We cannot judge if these documents are authentic. However, the documents are clearly stolen. The theft has been reported. The authorities are involved. We expressly advise that both the purchase and the publication of such documents and data is forbidden. The contents of any medical files are totally private and confidential and must not made available to the public.

"We will therefore, in every single case, press for criminal charges and damages against any publication of the content or reference to the medical file. We trust for your understanding."

Schumacher has been hospitalised since suffering a skiing accident in December.