In his remarks to the 600,000-strong crowd, the pope issued his strongest denunciation of religious intolerance yet in Cuba.
He referred to the biblical account of how people persecuted by the Babylonian king "preferred to face death by fire rather than betray their conscience and their faith."
He said people find freedom when they seek the truth that Christianity offers.
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Nick Clegg will attempt to win over the female electorate when he kicks off the Liberal Democrats' general election campaign later today.
Up to £140 billion of savings could be released when over 55-year-olds are allowed to cash in their pension pots from April 6th.
The party's plans include a £2.5 billion Time to Care fund for the NHS, capping rail fare increases and 3,000 more midwives.