As the leaders of the world’s great powers gathered at a G8 meeting in Paris - with possible military action and imposing a no-fly zone over Libya high on the agenda - the regime's troops were continuing their advance, taking back cities that had been in the hands of anti-government rebels. Gaddafi's forces have swept eastwards with a wave of strikes by war planes, tanks and battleships. The army now has rebel-held Benghazi in its sights.