An academic panel investigating the work of South Korean researcher Hwang Woo-suk found that he faked his landmark claim to have cloned human embryonic stem cells — capping the spectacular fall of a man once lauded as a pioneer in the field.

The latest revelation Tuesday by an investigating panel at Seoul National University was sure to be a huge disappointment to scientists and patients alike.

Hwang's breakthrough cloning claim had offered hope to millions of people suffering from debilitating ailments, such as Alzheimer's disease, Parkinson's disease and AIDS.

It followed a finding by the same panel last month that Hwang's claim in 2005 to have developed 11 patient-specific stem cell lines was also false.

Hwang "did not have any proof to show that cloned embryonic stem cells were ever created," the panel said in a report, disputing claims in Hwang's 2004 paper in the journal Science. In the paper, Hwang said he had cloned a human embryo and extracted stem cells from it.

However, the panel upheld Hwang's claims last year to have created the world's first cloned dog, an Afghan hound named Snuppy. That achievement was not regarded as important as the cloning of human cells, however, as various animals had already been cloned.

Scientists hope to someday use human stem cells — master cells that can grow into any body tissue — to battle a number of diseases. Creating stem cells genetically matched to a specific patient would be a breakthrough because they would not be rejected by the patient's immune systems.

But despite years of research, Hwang was the only person to claim success in extracting the cells from an embryo.

"The 2004 paper was written on fabricated data to show that the stem cells match the DNA of the provider although they didn't," the report said.

The reputation of Hwang — once dubbed "The Pride of Korea" — has eroded steadily in recent months with increasing questions about his work.

In December, a devastating report by the university, where Hwang conducted much of his research, concluded that he had fabricated another article published in Science last year.

The university's nine-member investigative panel said it could not find any of the 11 stem cell lines matched to patients, as Hwang had reported in that research.

Science has said it would retract that May 2005 paper and investigate Hwang's 2004 paper that claimed the first cloned human embryo.

Hwang had also come under fire for using eggs in his studies donated by junior researchers on his team.

He conceded in November that two subordinate scientists had donated eggs without his knowledge and that other women were paid to take fertility drugs to produce eggs for research. Both practices are viewed as coercive and unethical in the West.

The panel said Tuesday that one of the two researchers who donated eggs said that Hwang accompanied her to a clinic for the procedure. Hwang also received letters from female scientists on his team pledging to donate eggs, the panel said.

The concerns over the egg donations caused Hwang's sole American collaborator, University of Pittsburgh researcher Gerald Schatten, to end his 20-month partnership with Hwang's team in November. He also asked Science to remove him as senior author of Hwang's May 2005 paper.

Alan Trounson, a top stem cell researcher and expert in embryonic stem cells at Monash University in Melbourne, Australia, said he was "very, very disappointed."

"I just don't understand why a scientist would do something like that."

Hwang has not made any public appearances since last month when he said he would resign his faculty position, and his whereabouts are unknown. Hwang said earlier that despite any scandal over faked results, he has the technology to clone stem cells and could reproduce his experiments.

The university condemned his fabrications.

"This conduct cannot but be seen as an act that fools the whole scientific community and the public," Tuesday's report said. "Just based on the facts of the fabrications that have been disclosed, the penalty has to be severe."

Trounson said Hwang's fabrications will have a negative impact on research but added the field remains promising.

"I am very confident that embryonic stem cells will provide us with some very important new regenerative medicine strategy," he said. "It's just that we will have to wait a little longer."

Research such as Hwang's is off-limits in many U.S. labs because Washington restricts federal money for human embryonic stem cell experiments. Labs that depend on federal money cannot use it to create new embryonic cell lines as Hwang claimed he did.

A South Korean scientist said Hwang's downfall could give new impetus for other laboratories to push forward with stem-cell development.

It can "serve as an opportunity for other scientists to expedite research in the area," said Park Se-pill, a stem cell scientist who heads the Maria Infertility Medical Institute in Seoul.

Ordinary people expressed anger with Hwang, who has been a role model in a society that places great emphasis on education and scholarship.

"My daughter got really disappointed to learn that professor Hwang lied," said Park Jae-hyung, 48, visiting Seoul with his 12-year-old daughter on Tuesday from the southern port city of Busan. "I think this is the result of Koreans' hasty culture."

South Korean prosecutors are preparing their own investigation into Hwang's work. South Korean media have said that Hwang, who received massive government funding for his research, may also face charges of misappropriation of funds.

Hwang, 53, had become a national hero in South Korea before his scientific advances fell under question.

He was designated the country's first-ever "top scientist" in June by the government, winning special funding.

Korean Air even gave Hwang and his wife free first-class flights for a decade, calling the scientist a "national treasure."