A South Korean university panel has dealt another blow to once-celebrated scientist Hwang Woo-suk, ruling he faked all claims to have cloned human stem cells. But the experts confirm Hwang did clone the world's first dog last year.

On Tuesday, the head of a Seoul National University investigative panel, Jeong Myeong-hee, exposed another of Hwang Woo-suk's purported scientific breakthroughs as a sham.

Jeong says Hwang never produced the world's first cloned human embryos, as he claimed in 2004, and had fabricated the data for that research. Jeong also confirmed the scientist had not produced genetically tailored human stem cells, as claimed in 2005.

Tuesday's announcement is the culmination of a month-long probe into Hwang's work. It was initiated after South Korean TV reporters began producing revelations damaging to Hwang last November.

Hwang has admitted to ethical irregularities in his procuring human egg for research, and acknowledges he faked his 2005 report on tailored embryonic stem cells.

Stem cells are master cells that can grow into any other body tissue.

Hwang's 2005 claims to have developed 11 patient-specific stem cell lines had raised hopes for eventual therapies for spinal injuries, Alzheimer's and other diseases.

However, Jeong did verify Tuesday that Hwang had cloned the world's first dog - introduced last year to the world as "Snuppy."

Jeong says the panel was able to conclude that Snuppy was genetically identical to "Ty", the Afghan Hound from which Hwang and his team extracted source cells.

Hwang has not yet responded to Tuesday's announcement about his 2004 work. However, he has maintained he possesses the basic technology for extracting human stem cells from cloned embryos. He accuses the hospital that collaborated with his team of tampering with his research - an allegation the hospital denies.

Hwang has resigned all of his official positions. Seoul National University is expected to announce sanctions against the former professor on Wednesday.

Hwang may also face criminal charges because he received millions of dollars in research funding from the South Korean government.