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US intercepts 'ricin' letter to Obama US intercepts 'ricin' letter to Obama
(35 minutes later)
A letter addressed to US President Barack Obama containing a "suspicious substance" has been intercepted.A letter addressed to US President Barack Obama containing a "suspicious substance" has been intercepted.
Initial tests on the letter, identified at a remote facility, showed the presence of the lethal toxin ricin.Initial tests on the letter, identified at a remote facility, showed the presence of the lethal toxin ricin.
The US Secret Service said the letter arrived at the facility on 16 April, the same day a letter intended for a US senator tested positive for ricin. The letter, which arrived at the facility on 16 April, is related to another laced with ricin intended for a US senator, the FBI said.
Meanwhile, US Capitol Police are questioning a suspect in connection with the tainted letters, reports say.Meanwhile, US Capitol Police are questioning a suspect in connection with the tainted letters, reports say.
In a separate development, areas within two senate office buildings have been cleared over suspicious letters. The Federal Bureau of Investigation (FBI) said the letters addressed to the president and Republican Senator Roger Wicker were both were postmarked Memphis, Tennessee and dated 8 April.
The letter addressed to the president has tested positive for ricin, according to US media reports, but the contents are being sent to an accredited laboratory for further analysis, as the preliminary results need further verification. The contents of the letter intended for President Obama are being sent to an accredited laboratory for further analysis, the FBI said, with results expected in 24 to 48 hours.
All congressional mail has been sorted and tested off-site since anthrax was posted to two senators in 2001. While there is a heightened sense of alert in the capital after Monday's deadly bomb attacks at the Boston marathon, the FBI said there was "no indication of a connection".
A spokesman for the Secret Service, which protects the US president and his family, said it was liaising with the US Capitol Police and Federal Bureau of Investigation (FBI) to trace the origins of the letter. All congressional mail has been sorted and tested off-site since letters laced with anthrax were posted to two senators in 2001.
"This facility routinely identifies letters or parcels that require secondary screening or scientific testing before delivery," Edwin Donovan said. A spokesman for the Secret Service, which protects the US president and his family, said it was liaising with the US Capitol Police and the FBI to trace the origins of the letters.
The letter intercepted on Tuesday was intended for Roger Wicker, a Republican senator representing Mississippi.
Ricin, extracted from castor beans, is 1,000 times more toxic than cyanide.Ricin, extracted from castor beans, is 1,000 times more toxic than cyanide.
It can be fatal when inhaled, swallowed or injected, although it is possible to recover from exposure.It can be fatal when inhaled, swallowed or injected, although it is possible to recover from exposure.
Correspondents say there is a heightened sense of alert in the capital after the deadly bomb attacks at the Boston marathon but there is no indication so far of any connection between the two incidents.