A daily in Seoul says scientist Hwang Woo-suk stands by his cloning thesis published in May and wants a probe into whether his stem cells were switched.

The Buddhist newspaper Beopbo on Saturday quoted Hwang as saying he is certain of the switch and that experts will be able to tell the difference.

He said a prosecution probe will take only two days.

Hwang has alleged that his former assistant Kim Sun-jong, who has admitted to manipulating photos of DNA carried in Hwang's paper, could have swapped Hwang's stem cells with fertilized eggs from MizMedi Women's Hospital.