Delegates at a major international conference on the sexual exploitation of children have described the internet as a playground for paedophiles.

One delegate, the director of Save the Children in Canada, said her own daughter had nearly become a victim.

Addressing the conference in the Japanese city of Yokohama, Jeane Elise Parlee said her daughter had run away from home after being befriended in an internet chat room.

There has been a massive growth in the use of the internet since the last conference, five years ago in Sweden.

The battle now is for law enforcement agencies to develop the technology to fight back.

One expert, John Carr, of End Child Prostitution in Asian Tourism, said only 20 police forces in the world had the technical capability to tackle cyber-pornography.

From the newsroom of the BBC World Service