(CNN) -- Thrust into the headlines last week, accused of sending ricin-tainted letters to President Barack Obama and two other officials, Paul Kevin Curtis is a free man again. "It's like a train has been lifted off my shoulders," Curtis told CNN's "Piers Morgan Live" on Tuesday. "I'm overwhelmed. I'm extremely happy to be vindicated and out and able to see my kids." Charges were dropped and "new information" became available, U.S. Attorney Felicia Adams said. Authorities are investigating whether someone may have tried to falsely implicate the Elvis impersonator from Corinth, Mississippi, a law enforcement source said on condition of anonymity.
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"I'm overwhelmed. I'm extremely happy to be vindicated," he says
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New information has come to light, U.S. attorney says
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Source says investigators are looking at someone trying to frame him
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Curtis had been accused of mailing the poison to Obama, a U.S. senator and a judge
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