U.S. ricin attack

Paul Kevin Curtis, the suspect arrested  for sending potentially

poison-laced letters intended for President Barack Obama and Republican

Sen. Roger Wicker of Mississippi, was released from jail April 22.

Federal agents wearing hazardous material suits and breathing apparatus inspect the home and possessions in the West Hills Subdivision house of Paul Kevin Curtis in Corinth, Miss., Friday, April 19, 2013. Curtis is in custody under the suspicion of sending letters covered in ricin to the U.S. President Barack Obama and U.S. Sen. Roger Wicker, R-Miss. (AP Photo/Rogelio V. Solis)
Federal agents wearing hazardous material suits and breathing apparatus inspect the home and possessions in the West Hills Subdivision house of Paul Kevin Curtis in Corinth, Miss., Friday, April 19, 2013. Curtis is in custody under the suspicion of sending letters covered in ricin to the U.S. President Barack Obama and U.S. Sen. Roger Wicker, R-Miss. (AP Photo/Rogelio V. Solis)
Federal agents wearing hazardous material suits and breathing apparatus inspect the home and possessions in the West Hills Subdivision house of Paul Kevin Curtis in Corinth, Miss., Friday, April 19, 2013. Curtis is in custody under the suspicion of sending letters covered in ricin to the U.S. President Barack Obama and U.S. Sen. Roger Wicker, R-Miss. (AP Photo/Rogelio V. Solis)
A Prince George's County, Md. firefighter dressed in a protective suit walks out of a government mail screening facility in Hyattsville, Md., Wednesday, April 17, 2013. Police swept across the U.S. Capitol complex to chase a flurry of reports of suspicious packages and envelopes Wednesday after preliminary tests indicated poisonous ricin in two letters sent to President Barack Obama and a Mississippi senator. (AP Photo/Alex Brandon)
A Prince George's County, Md. firefighter dressed in a protective suit walks out of a government mail screening facility in Hyattsville, Md., Wednesday, April 17, 2013. Police swept across the U.S. Capitol complex to chase a flurry of reports of suspicious packages and envelopes Wednesday after preliminary tests indicated poisonous ricin in two letters sent to President Barack Obama and a Mississippi senator. (AP Photo/Alex Brandon)
A Prince George's County, Md. firefighter dressed in a protective suit walks out of a government mail screening facility in Hyattsville, Md., Wednesday, April 17, 2013. Police swept across the U.S. Capitol complex to chase a flurry of reports of suspicious packages and envelopes Wednesday after preliminary tests indicated poisonous ricin in two letters sent to President Barack Obama and a Mississippi senator. (AP Photo/Alex Brandon)
A Prince George's County, Md. firefighter dressed in a protective suit walks into a government mail screening facility in Hyattsville, Md., Wednesday, April 17, 2013. Police swept across the U.S. Capitol complex to chase a flurry of reports of suspicious packages and envelopes Wednesday after preliminary tests indicated poisonous ricin in two letters sent to President Barack Obama and a Mississippi senator. (AP Photo/Alex Brandon)
A Prince George's County, Md. firefighter dressed in a protective suit walks into a government mail screening facility in Hyattsville, Md., Wednesday, April 17, 2013. Police swept across the U.S. Capitol complex to chase a flurry of reports of suspicious packages and envelopes Wednesday after preliminary tests indicated poisonous ricin in two letters sent to President Barack Obama and a Mississippi senator. (AP Photo/Alex Brandon)
A Prince George's County, Md. firefighter dressed in a protective suit walks into a government mail screening facility in Hyattsville, Md., Wednesday, April 17, 2013. Police swept across the U.S. Capitol complex to chase a flurry of reports of suspicious packages and envelopes Wednesday after preliminary tests indicated poisonous ricin in two letters sent to President Barack Obama and a Mississippi senator. (AP Photo/Alex Brandon)
This undated photo obtained from the facebook page of Paul Kevin Curtis, shows, according to neighbors, Paul Kevin Curtis, 45. Curtis was arrested Wednesday, April 17, 2013, at his home in Corinth, near the Tennessee state line. He is accused of mailing letters with suspected ricin to to national leaders. (AP Photo)
This undated photo obtained from the facebook page of Paul Kevin Curtis, shows, according to neighbors, Paul Kevin Curtis, 45. Curtis was arrested Wednesday, April 17, 2013, at his home in Corinth, near the Tennessee state line. He is accused of mailing letters with suspected ricin to to national leaders. (AP Photo)
This undated photo obtained from the facebook page of Paul Kevin Curtis, shows, according to neighbors, Paul Kevin Curtis, 45. Curtis was arrested Wednesday, April 17, 2013, at his home in Corinth, near the Tennessee state line. He is accused of mailing letters with suspected ricin to to national leaders. (AP Photo)
A City of Corinth police car prevents access to a house in the West Hills Subdivision in Corinth, Miss. on Thursday morning, April 18, 2013. Law enforcement officials were blocking off the dwelling after taking Paul Kevin Curtis of Corinth, Mississippi into custody Wednesday under the suspicion of sending letters covered in ricin to U.S. President Barack Obama and Mississippi Sen. Roger Wicker (R-MS). Curtis was arrested at his home in Corinth, Mississippi, and is "believed to be responsible for the mailings of the three letters sent through the U.S. Postal Inspection Service which contained a granular substance that preliminarily tested positive for ricin," the Justice Department said in a statement. (AP Photo/Rogelio V. Solis)
A City of Corinth police car prevents access to a house in the West Hills Subdivision in Corinth, Miss. on Thursday morning, April 18, 2013. Law enforcement officials were blocking off the dwelling after taking Paul Kevin Curtis of Corinth, Mississippi into custody Wednesday under the suspicion of sending letters covered in ricin to U.S. President Barack Obama and Mississippi Sen. Roger Wicker (R-MS). Curtis was arrested at his home in Corinth, Mississippi, and is "believed to be responsible for the mailings of the three letters sent through the U.S. Postal Inspection Service which contained a granular substance that preliminarily tested positive for ricin," the Justice Department said in a statement. (AP Photo/Rogelio V. Solis)
A City of Corinth police car prevents access to a house in the West Hills Subdivision in Corinth, Miss. on Thursday morning, April 18, 2013. Law enforcement officials were blocking off the dwelling after taking Paul Kevin Curtis of Corinth, Mississippi into custody Wednesday under the suspicion of sending letters covered in ricin to U.S. President Barack Obama and Mississippi Sen. Roger Wicker (R-MS). Curtis was arrested at his home in Corinth, Mississippi, and is "believed to be responsible for the mailings of the three letters sent through the U.S. Postal Inspection Service which contained a granular substance that preliminarily tested positive for ricin," the Justice Department said in a statement. (AP Photo/Rogelio V. Solis)
A Prince George's County, Md. firefighter, left, gets dressed in a protective suit before going into a government mail screening facility in Hyattsville, Md., Wednesday, April 17, 2013. Police swept across the U.S. Capitol complex to chase a flurry of reports of suspicious packages and envelopes Wednesday after preliminary tests indicated poisonous ricin in two letters sent to President Barack Obama and a Mississippi senator. (AP Photo/Alex Brandon)
A Prince George's County, Md. firefighter, left, gets dressed in a protective suit before going into a government mail screening facility in Hyattsville, Md., Wednesday, April 17, 2013. Police swept across the U.S. Capitol complex to chase a flurry of reports of suspicious packages and envelopes Wednesday after preliminary tests indicated poisonous ricin in two letters sent to President Barack Obama and a Mississippi senator. (AP Photo/Alex Brandon)
A Prince George's County, Md. firefighter, left, gets dressed in a protective suit before going into a government mail screening facility in Hyattsville, Md., Wednesday, April 17, 2013. Police swept across the U.S. Capitol complex to chase a flurry of reports of suspicious packages and envelopes Wednesday after preliminary tests indicated poisonous ricin in two letters sent to President Barack Obama and a Mississippi senator. (AP Photo/Alex Brandon)

What to Read Next