Everett Dutschke arrested in case of ricin letters sent to President Barack Obama after Elvis impersonator released

Suspect, who ran for the Mississippi legislature in 2007, will appear in court on Monday

Everett Dutschke has been arrested over the poison letters sent to Barack Obama and two other politicians (AP)

The main suspect has been arrested in the case of the poison letters sent to Barack Obama and two other politicians.

Everett Dutschke, 41, was charged yesterday with "knowingly developing, producing, stockpiling, transferring, acquiring, retaining and possessing a biological agent, toxin and delivery system, for use as a weapon, to wit: ricin."

Dutschke's attorney said she had no comment. Earlier this week she said Dutschke was cooperating fully with investigators that he has insisted he had nothing to do with the letters. He was arrested about 12:50 a.m. at his home and is expected in court Monday. If convicted, he faces up to life in prison.

The letters, which tested positive for ricin, were sent earlier this month to Obama, Senator Roger Wicker of Mississippi and Mississippi judge, Sadie Holland.

On Tuesday an Elvis impersonator was released from a Mississippi jail and charges against him were dropped. Paul Kevin Curtis, 45, is known to have a long-running feud with Dutshcke.

Earlier, police had searched Dutschke's home in Tupelo, north-east Mississippi. They later searched a martial arts studio he used to run.

Curtis, who performs as Elvis and other celebrities, described a long feud between himself and Dutschke, but said he's not sure exactly what started it. Dutschke insists he had nothing to do with the letters, which contained language identical to that found on Curtis' Facebook page and other websites, making him an early suspect.

Both men say they have met Wicker, and they each have a connection to Holland, who received one of the ricin letters. Hers was the only one to make it into the hands of an intended target. Her son Steve Holland, said his mother did a "smell test" of the envelope and a substance in it irritated her nose. Mr Holland himself is a member of the Mississippi House of Representatives, who defeated Dutschke in a one-sided 2007 election.

The judge was not harmed by what authorities say was a crudely made form of the poison, which is derived from castor beans.

Holland was presiding judge in a case in which Curtis was accused of assaulting a Tupelo attorney in 2003. She sentenced Curtis to six months in the county jail, of which he served only part, according to his brother.