Newborn babies have purportedly been advertised for sale on the popular mainland website Eachnet, an online auction system owned by US-based eBay.
In the advertisement, a person based in Henan province using the moniker 'Forever Innovator', offered to 'provide infant boys for 28,000 yuan each and newborn girls for 13,000 yuan each'.
The advertisement promised the babies would be delivered within 100 days of birth.
A Shanghai police spokeswoman said a probe was under way.
'We may work with police in other provinces if necessary,' she said.
The website's headquarters in Shanghai reported the advertisement to police after a web surfer complained after seeing the baby offer in the site's car ornaments category on Tuesday.
Lion Tang Lei, eBay's Shanghai spokesman, said: 'We blocked the page right after we noticed it and reported it to the police.'
