Face the Facts - Feeding Frenzy

Two years ago spiralling prices of wheat, corn and rice caused riots in more than 30 countries worldwide as many families struggled to feed themselves. A number of organisations, including representatives at the UN, believe that it wasn't just a supply and demand issue, but that financial firms and other speculators entered the food markets to profit from short term changes in price. As food prices begin to rise again, John Waite investigates whether speculators are to blame, and if tighter regulation is needed.