letters that were mailed to president obama and other officials. The main suspect has been released from jail. Charges have been dropped against him. And there's now questions about whether or not he... See More
letters that were mailed to president obama and other officials. The main suspect has been released from jail. Charges have been dropped against him. And there's now questions about whether or not he was framed. Abc's matt gutman is in oxford, mississippi, with the latest on this story. Good morning to you, matt. Reporter: Good morning, elizabeth. That suspect, an elvis impersonator, who was thought to be the mastermind behind that poisonous plot against the president, he walked out of that courthouse just yesterday. Now, the fbi is focusing on his rival, a karate instructor. Overwhelming. To say the least. It's overwhelming. Reporter: This morning, kevin curtis, a celebrity impersonator, who was acced of mailing the deadly toxin ricin, to president obama and other politicians, and terrorizing the federal government, for two days lasts now a free man. When you've been charged with something and you just -- you never heard of ricin or whatever. I thought they said rice. I said, I don't even eat rice. Reporter: After nearly a week in jail, the charges of threatening the life of the president and others, suddenly dropped. His lawyer says he was framed. Very diabolical to me. Very frightening. Reporter: Now, authorities have switched their focus from the elvis impersonator to a karate instructor. The fbi swarmed the house of a man who ran for a seat in the house of representatives. He hasn't been charged in the ricin case. In this picture, he is seen with senator wicker, one of the recipients of those ricin letters. The alleged feud goes back years. In 2007, it seemed to get ugly. He apparently was posting a videotape on youtube, implying curtis was tearing down his campaign signs. And just a couple of weeks ago, curtis reported on twitter that he had been charged with molestation. This mug shot was taken from that arrest. But the pair has some things in common. They're both musicians. Curtis, of course, partial to elvis and prince. Both also practice martial arts. They have something else in common. Both claim to be geniuses, members of mensa. They said, both of them, they had nothing to do with the ricin-laced letters sent to the president and others. And now, the attorney is saying he's cooperating fully with the investigation. Both claim to be geniuses. Okay. But getting back to the charges that the first man was framed. Are there any charges about any evidence to support that? I mean -- Reporter: Not really. What we've learned from the investigation so far, is that that ricin was not weaponized. Meaning, it couldn't really hurt someone unless you inhaled a lot of it. What's clear, only, is that somebody's walking out there who mailed ricin-laced letters to the president and others. And the fbi doesn't know exactly who that is right now.
This transcript has been automatically generated and may not be 100% accurate.