A former colleague of embattled South Korean scientist Hwang Woo-suk said today he has asked his university to widen its investigation into the stem cell researcher’s work, and to review earlier purported breakthroughs.

South Korean researcher Hwang Woo-suk stood by his purported breakthroughs in stem cell technology today despite accusations he falsified key evidence.

A doctor who provided human eggs for research by cloning pioneer Hwang Woo-suk claimed today that the South Korean scientist admitted most of the stem cells he produced and documented in a journal article were faked, according to news reports.