Seoul National University professor Hwang Woo-suk has reportedly admitted to fabricating stem cell research results that were published in the U.S. journal Science.

According to a report by local daily Hankyoreh, the stem cell expert also asked Science to retract his stem cell research paper.

The paper quoted a medical official, Roh Sung-il, as saying that Hwang had indeed made such remarks. Roh is the administrator of MizMedi Hospital, which provided the human ova for Hwang's research.

Roh, who was also a co-author of Hwang's stem cell research paper published by Science in May, met the embattled scientist at Seoul National University hospital Thursday morning.

The administrator told reporters that the university no longer needs to reexamine the accuracy of the research, adding, "It's time for Hwang himself to explain the entire matter."

He was also quoted by KBS as saying that there were no stem cells cloned by Hwang's research team.

Roh said, "Of the 11 alleged embryonic stem cells described in Hwang's study, nine are fake, with the authenticity of the two others yet to be confirmed."

Hwang has been treated as a national hero in his native South Korea for his groundbreaking work in cloning technology, which earlier this year produced the world's first cloned dog and apparently the first-ever cloning of human embryos.

In the controversial paper published in Science in May, Hwang claimed that he had cloned 11 human embryos and cultivated patient-specific stem cell lines from them.