A man has been arrested in connection with the sending of letters containing the poison ricin to US officials including President Obama.
Paul Kevin Curtis was detained in Mississippi. All the letters were post marked Memphis, Tennessee.
They were prevented from reaching their targets after they tested positive for the lethal toxin at a government mail-screening facility.
Officials have been quick to deny any link to the Boston Bombings. Back in 2001 after the 9/11 attacks there was a wave of letters containing anthrax
Ricin, can be fatal when inhaled, swallowed or injected.