The Internet site of a South Korean stem cell center overloaded Tuesday as it began accepting applications from people with Parkinson's disease and spinal cord injuries who want to participate in research.

An official at the World Stem Cell Hub said the Web site slowed to a crawl, because there were too many access attempts for about three hours.  The official said normal operation resumed later.

He said computer experts were on standby in case of sabotage by those who oppose stem cell research and cloning technology.

The South Korean stem cell bank opened October 19 with the aim of providing scientists around the world with embryonic stem cells.

These cells are seen as a potential source of replacement tissue for people with a variety of ailments.

Some information for this story provided by Reuters and AP.