WASHINGTON :USauthorities said Saturday they have arrested a man as part of a probe into poison-laced letters sent to President Barack Obama and other public officials.

Special agents took James Everett Dutschke into custody “without incident” at his home in Tupelo, Mississippi, around 12:50 Saturday morning, a spokeswoman for the Federal Bureau of Investigation told AFP.

Scott Floyd of the Tupelo Police Department had earlier also confirmed the arrest. Further details were not immediately available.

Three letters laced with ricin were discovered last week as the nation was reeling from a deadly bombing at the Boston Marathon. They were addressed to Obama, Republican Senator Roger Wicker of Mississippi and a justice of the peace in the same US state, Sadie Holland.

Authorities had initially arrested another man, Paul Kevin Curtis, in the case but the charges against him were later dismissed and he was released from jail.

Investigators suspected Curtis because he had written publicly about an alleged black market for the illegal sale of human body parts that he thought was being covered up by the government.

But his attorney insisted from the get-go that Curtis was framed and pointed the finger at Dutschke, who reportedly had a long-standing dispute with the Holland family.

Dutschke, however, insisted Curtis had implicated him in order to dodge his own guilt.

“I guess Kevin got desperate. I feel like he’s getting away with the perfect crime,” he told the Clarion Ledger newspaper earlier this week.

“It has made my family incredibly unsafe. It has put a target on us, and it was reckless and irresponsible,” he was quoted as saying.

“The phone has been ringing off the hook, with calls and hang-ups and all sorts of horrible things.”