Scant evidence in US ricin case: lawyer FEDERAL authorities have produced scant evidence linking a Mississippi man to the mailing of ricin-laced letters to the US president and a senator, his lawyer says. Christi McCoy said after a court hearing on Friday that the government has offered no evidence to prove her client, Paul Kevin Curtis, had possession of any ricin or the source from which it is extracted - castor seed. An FBI agent testified during the hearing that he could not say if investigators had found ricin at Curtis' home, and McCoy said the evidence linking the 45-year-old man to the crime so far has hinged on his writings posted online. He is adamant that he did not do this, and she said she has seen nothing to prove him wrong. Curtis was ushered into the courtroom before the hearing began in an orange jail jumpsuit and shackles. He turned to face his daughter in the audience before the hearing and whispered, "I didn't do it." Prosecutors had wanted to delay the hearing because searches of Curtis' home and car had not been completed and DNA and other tests are pending. Curtis' brother Jack Curtis and 20-year-old daughter Madison Curtis watched the court proceeding and said afterward they are not convinced he did what he is accused of, even though they tried to keep an open mind about what would be presented. "After hearing what I heard in this courtroom, it appears to me that the reason I haven't been provided any evidence is there appears to be none that would link my brother directly to the charges that have been made," Jack Curtis said after the hearing. So far, Paul Kevin Curtis is the primary focus for investigators and the only person arrested in connection with sending those letters and a third threatening letter mailed to a judge. But during a hearing on Friday, FBI agent Brandon M. Grant testified that authorities were still trying to determine whether there were any co-conspirators. As the hearing went on for roughly two hours, Grant said under questioning by Curtis' attorney that he could not say whether any ricin had been found at Curtis' home because the investigation was ongoing. Investigators had found a package they were interested in, but Grant said he did not know what was in it. Grant testified that there were indentations on the letters from where someone had written on another envelope that had been on top of them in a stack. The indentations were analysed under a light source and turned out to be for Curtis' former addresses in Booneville and Tupelo, Grant said. Grant also testified that there was one fingerprint on the letter sent to the judge but that it didn't match Curtis. He said several people handled the letter, and DNA and other tests are pending. Curtis' lawyer peppered the agent with questions in an attempt to show the government had little hard evidence, but Grant said people's lives were at risk and it wasn't like a fraud investigation in which authorities could gather more evidence before making an arrest. Family and acquaintances have described Curtis as a caring father and enthusiastic musician who struggled for years with mental illness. Curtis is an Elvis impersonator and performed at parties. Friends and relatives also say he spiraled into emotional turmoil trying to get attention for his claims of uncovering a conspiracy to sell body parts on the black market. Grant testified that Curtis' family had become increasingly concerned by his behavior. Grant said Curtis' ex-wife told authorities that he fought with his daughter around Christmas and told her, "Maybe I should go ahead and kill you." Madison Curtis said after the hearing that she loves her father and stands by him. Grant's testimony ended on Friday evening, but the hearing is set to continue on Monday morning. In court documents, Curtis' lawyer gave some details of his arrest. Curtis had gone to get his mail outside his home and was planning to go to his ex-wife's home to cook dinner for her and their children when he was approached by officers in SWAT gear, she wrote. He was then interrogated at an FBI office for several hours, handcuffed and chained to a chair. Curtis cooperated to the best of his ability, but when he suggested he might need a lawyer, an agent discouraged that, McCoy wrote. According to an FBI affidavit, the letters he sent read: "Maybe I have your attention now even if that means someone must die." Officials have confirmed that the letters contained ricin but the FBI has not yet revealed details about how the ricin was made or how lethal it may have been.