MySpace, Facebook and other online social networking sites will meet some of their fiercest critics head-on today for the first time, as pressure mounts on these hugely popular web destinations to limit the risks to young people from online sexual predators.

A New York conference, organised by the US National Center for Missing and Exploited Children (NCMEC), comes amid growing reports of children being fooled into having conversations with, exchanging pictures with, or even meeting people through social networking sites who turn out to have used a false identity to lure them in.