Suspicious letter addressed to US President Obama has tested positive for the deadly poison ricin, as did a letter to a Republican Senator.
The FBI assessment is that there are no links between the poison letters to Obama and Senator Roger Wicker and the bombs at The Boston Marathon.
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Atheist Richard Dawkins has cancelled his Australia and New Zealand tour after suffering from a 'minor stroke', his management said.
Sleet and snow for some parts of Scotland. Elsewhere in the UK will be cold, cloudy and with some showers.
At least 52 people have been killed after a fight broke out between two rival drugs gangs in a Mexico prison.