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.
More top news
Andreea Cristea's partner Andrei Burnaz was due to propose to her on the day she was pushed by a car into the river Thames.
ITV News reveals new details of how claims of misbehaviour at British Cycling were all but ignored despite being uncovered over years ago.
Travis Frain is recovering in hospital and has posted a photo to Twitter of Prince Charles by his bedside.