A man has been arrested in Mississippi in connection with the sending of letters containing ricin to President Barack Obama, a senator and a judge, BBC News reported.

Everett Dutschke was detained at his home in Tupelo at 01:00 (06:00 GMT) on Saturday, April 27, and handed over to the U.S. Marshals Service, police said.

Dutschke's home and former place of business were searched this week. He has links to a man against whom charges were filed and later dropped, as well as the senator and judge.

Ricin is a naturally occurring protein, found in the castor oil plant, which is highly toxic. It is 6,000 times more poisonous than cyanide.

Tupelo Police Chief Tony Carleton said Dutschke was taken into custody without incident on Saturday. His home had been under surveillance since Friday afternoon.

A law enforcement official told WTVA that the 41-year-old was being held at the Lafayette County Detention Center, and that he would not appear in U.S. District Court until Monday.

Agents from the FBI and the U.S. Capitol Police, as well as members of an anti-terrorist response team from the Mississippi National Guard, searched Dutschke's home on Tuesday and Wednesday, as well as the premises of a former martial arts studio he ran in Tupelo.

Attention turned to Dutschke after charges were dropped on Tuesday against Paul Kevin Curtis, a local Elvis impersonator.

A search of Curtis' home in nearby Corinth revealed no evidence to suggest he had sent the ricin-laced letters to President Obama, Senator Roger Wicker and Mississippi Judge Sadie Holland, officials said.

Hal Neilson, a lawyer for Curtis, said he had named Dutschke on a list of people who might have had a reason to hurt his client. Prosecutors "took it and ran with it," he added.