Fox News reporter Chad Pergram has tweeted that the letter sent to Barack Obama and the letter sent to Senator Roger Wicker yesterday - which tested positive for the poison ricin - contained 'similar language' and were 'signed identically'.
Letters sent to Obama & Wicker contain similar language and are signed identically.
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Most of the UK will have a mixture of sunny spells and scattered showers before becoming drier in the afternoon.
Scottish people celebrate the birthday of national writer Robert Burns with events including haggis throwing and the Big Burns Supper.
There will be a rare chance to see an asteroid pass so close to the Earth you will be able to see it with binoculars on Monday night.