용의자의 이름은 폴 케빈 커티스로 이날 오전 5시 15분, 미시시피주의 본인의 자택에서 체포됐다.
커티스가 오바마 대통령을 비롯한 로저 위커 연방 상원의원과 미시시피주 법원 관리에게 보낸 괴편지에는 알갱이 모양의 물질이 들어있었다. 초기 조사에서 이는 리친 양성 반응을 보였으며 앞으로 48시간 내에 심층검사에 들어갈 예정이다.
오바마 대통령 수신의 편지는 화요일(현지시간) 백악관에서 다소 떨어진 외부 우편물 검사 시설에서 검열됐으며 같은 날, 위커 연방 상원의원에게 수신된 편지도 전달되기 전 의회 보안당국의 우편물 검색과정에서 리친 양성반응을 보였다고 한다.
편지에 “나는 KC이고 이 편지를 승인한다”라는 메시지가 써있었다.
리친은 호흡을 통해 체내로 유입되거나 혈류에 흡수될 경우 입자 한 개만으로도 사망에 이를 수 있을 정도로 치명적인 독성물질이다.
상원의원 칼 레빈 또한 미시간 주 지사에서 한 직원이 “수상하게 생긴 편지”를 발견해 수사요청을 한 상태라고 했다. 직원에게 증상이 나타나진 않았지만 예방조치를 위해 그는 병원에서 하룻밤을 보냈다고 한다.
이에 더해, 두 동의 상원건물에도 수상한 소포가 배달되어 일시적으로 건물 출입이 금지 됐지만 위험물질은 없었다고 한다.
FBI에 따르면 괴편지 배달 사건은 계속 수사 중이지만, 16일 보스톤 마라톤대회에서 발생한 테러 사건과는 연관성이 없는 것으로 보인다고 한다. (코리아 헤럴드)
<관련 영문 기사>
Suspect arrested in US over Obama ricin letter
A letter addressed to President Barack Obama tested positive for ricin, and authorities arrested a suspect, stoking alarm in Washington on Wednesday after an earlier scare over poisoned mail.
The FBI said there was no connection between blasts at the Boston marathon that killed three people on Monday and mailings sent to Obama, Republican Senator Roger Wicker and an unidentified Mississippi justice official.
Special agents on Wednesday afternoon arrested Paul Kevin Curtis, “the individual believed to be responsible for the mailings of the three letters sent through the US Postal Service,” the bureau said.
The letters “contained a granular substance that preliminarily tested positive for ricin,” it added in a statement.
Earlier reports had said that the letters to Obama and Wicker, which never reached them, were signed “I am KC and I approve this message.”
Curtis was arrested at his home in Corinth, Mississippi, according to the FBI.
After preliminary tests on the Obama letter showed traces of ricin, further examinations are to be carried out in the next 24 to 48 hours, the FBI said.
The US Secret Service said the letter to Obama had been intercepted at a mail screening site on Tuesday, the same day authorities said a letter sent to Wicker also showed traces of ricin.
Ricin -- a highly toxic protein found in castor beans -- can, when inhaled, cause respiratory problems. Ingested orally, it is lethal in even minuscule quantities.
Secret Service spokesman Edwin Donovan said the agency, which protects the president and his family, was working closely with the US Capitol Police and the FBI to trace the origins of the letter.
A filter at a second mail facility had tested positive for ricin, according to the FBI, which warned that more letters could be received.
But it added: “There is no indication of a connection to the attack in Boston.”
Senator Carl Levin, meanwhile, issued a statement saying one of his staffers had discovered a “suspicious-looking letter” at a regional office in Michigan and handed it over to authorities for further investigation.
The staffer had no symptoms, but was being held in hospital overnight as a precaution, the senator said.
Adding to nervousness in the US capital, two Senate office buildings were briefly cordoned off amid reports of a suspicious package, but were reopened after an all-clear was given.
US Capitol Police confirmed one man was being questioned.
“Right now, they are interviewing a person but that person is not in custody. He has not been detained,” a Capitol Police officer told AFP.
Republican Senator Jim Risch said everyone on Capitol Hill was perpetually as “vigilant as they can be” and that such scares had been part of life for many years.
The poisoned mailings recalled the mysterious series of letters laced with anthrax sent to lawmakers and some journalists, which killed five people and sickened 17 others, following the September 11 attacks in 2001.
Congressional mail has been screened off-site ever since.
Three Senate office buildings were shut in 2004 after tests found ricin in mail that had been sent to the Senate majority leader‘s office.
The biological agent was also sent to the White House and the Department of Transportation in November 2003. There were no injuries in those incidents. (AFP)