With one of the core members of Seoul National University professor Hwang Woo-suk's research team stationed at the University of Pittsburgh disappearing, emergency alert has been initiated because of fears of a possible leak of stem cell technology.

With this alert, key members of Hwang's team have abruptly left for the University of Pittsburgh, adding yet another level of tension to the saga.

"For the last two weeks we have been unable to contact Park Eul-soon, one of the members of the team that was stationed at the University of Pittsburgh to work" with Hwang's erstwhile collaborator Gerald Schatten there, an insider with the SNU team said. "The whole atmosphere coming from the U.S. team is strange." Schatten last month publicly severed ties with Hwang over ethical flaws in the team's procurement of human egg cells.

Park was originally supposed to return to Korea on Nov. 17 "but for some reason gave the impression that she intended to remain in the U.S.," the insider said. "We are looking into the situation." On the same day, SNU Prof. Ahn Cu-rie and Prof. Yoon Hyun-soo from Hanyang University caught a Korean Air flight to Chicago. The two professors are scheduled to fly on to Pittsburgh on Friday.

Park is a researcher who holds knowledge of key techniques for the removal of an egg cell's nucleus and transferring the nucleus of somatic cell into the egg cell. The researcher made a key contribution to the extraction of a stem cell line from the world's first cloned human embryo, the subject of a Hwang article in Science. The researcher was then dispatched to collaborate with Prof. Schatten's research team at the University of Pittsburgh. Park also played a crucial role in generating cloned monkey embryos.

But it was the fact that Park donated her own ova for the 2003 project that was at the heart of the current scandal that led to Hwang's resignation from all official posts.

If the researcher wants to stay in a U.S. university to collaborate with the local team instead of returning to Korea, there is likely to be concern over the possible leak of key technical knowledge.