WASHINGTON – Caught in the middle of a small town Mississippi feud, authorities dropped charges Tuesday against the man they had charged with sending ricin-laced letters to the White House, a U.S. senator and a county judge as the FBI appeared to turn its attention toward his longtime antagonist.

A federal magistrate judge directed that charges against Paul Kevin Curtis dismissed because “the ongoing investigation has revealed new information,” according to his written order. The charges were dropped without prejudice, meaning they could be lodged again in the future.

But James Everette Dutschke of Tupelo, Mississippi, said the FBI was searching his home in connection with the ricin letter case Tuesday afternoon. Dutschke said he was innocent and knows nothing about the ingredients for ricin.

The FBI in Mississippi and Washington, and the U.S. attorney’s office in Oxford, Mississippi, refused repeated requests to explain their about face on Curtis and whether they were now focusing on Dutschke as the man who might have sent three letters containing the deadly poison made from castor beans.

But it was clear that investigators now are dealing with two men with histories of erratic behavior whose conflict nearly came to blows, according to the account Curtis gave in a colorful, rambling news conference outside the federal courthouse in Oxford.

Curtis, 45, was released on bond, according to Jeff Woodfin, chief deputy of the U.S. Marshals Service for the Northern District of Mississippi.

Curtis’s release came a day after an FBI agent told a court that a search of Curtis’s home turned up no ricin, nor did investigators find any evidence that he was making it. No other physical evidence tying Curtis to the ricin mailings was presented in two days of federal court hearings, and a third day of hearings was canceled Tuesday morning without explanation, The Associated Press reported.

Curtis appeared at a news conference early Tuesday evening outside the federal courthouse in Oxford with his attorney, Christi McCoy, who has strongly asserted Curtis’ innocence. McCoy said “it took a lot of planning, determination and patience” to carry out the ricin attacks.

“That is so not Kevin, to spend hours focused on making ricin,” she said.

Curtis was arrested last Wednesday at his home in Corinth, Mississippi, and charged with sending letters containing ricin to President Obama, Sen. Roger Wicker, a Mississippi Republican, and a county judge in Mississippi. The first letter, to Wicker, was discovered April 15.

According to an FBI affidavit supporting the charges, Curtis allegedly mailed three identical letters on yellow paper laced with a poison believed to be ricin. The letters alluded to a long-held conspiracy theory about the trafficking in human body parts that Curtis had sought to expose.

Ricin is made from castor beans, and authorities have long worried about its use by terrorists and others. But FBI agents testified this week that they found no castor beans at Curtis’s house nor any information on his computer that he was researching the poison.

The Lee County Courier reported in January that Dutschke, a martial arts instructor, had been charged with two counts of child molestation. He was later released on bond.