Mastercard Inc said on Sunday it was investigating allegations against Pornhub.com following a newspaper column which said many videos posted on the adult website depicted child abuse.

The New York Times column, written by Nicholas Kristof, described videos on Pornhub that the author said were recordings of assaults on unconscious women and girls.

"The issue is not pornography but rape. Let's agree that promoting assaults on children or on anyone without consent is unconscionable," Kristof wrote in the column published last Friday...