Several Nobel science prize committees in Sweden are being investigated for possible bribery, a special corruption prosecutor told AFP on Thursday.
The first case involves several members from the prestigious Nobel committees for medicine, physics and chemistry who visited China at the expense of the Chinese authorities.
Special corruption prosecutor Nils Erik Schultz said he had launched a preliminary investigation.
He said he was looking into "the cost, who went on the trip, where they went, what position they held and I want to see their itinerary too."
In addition, he was examining "why the Chinese wanted to invite these people to China, was there the possibility they thought they could influence them in any way."
The investigation is not currently examining any people specifically, but looking into the trip itself to begin with, he said.
No Chinese citizen has won a Nobel Prize for the past three years.
The Medicine Prize is awarded by the Nobel committee at the Karolinska Institute, while the Physics and Chemistry prizes are awarded by separate committees at the Royal Swedish Academy of Sciences.
The second corruption case involves Anglo-Swedish pharmaceutical company AstraZeneca, which earlier this year signed a sponsor agreement with two Nobel companies with close ties to the Nobel Foundation: Nobel Web and Nobel Media.
Half of this year's Nobel Medicine Prize went to Harald zur Hausen of Germany for his discovery of the human papilloma virus (HPV) that causes cervical cancer.
AstraZeneca receives royalties for the two available vaccines against HPV.
Schultz said he was gathering information on the case to determine whether the pharmaceutical company had any influence over the Medicine Prize committee's choice of this year's winners.
However, he has not yet decided to formally launch a preliminary investigation.
Each October, the winners of the Nobel prizes for medicine, physics, chemistry, economics and literature are announced in Stockholm while the winner of the Peace Prize is announced in Oslo.
The formal ceremonies take place on December 10.