LAS VEGAS _ A man authorities suspect was poisoned by ricin found in his motel room pleaded not guilty Friday to possession of a biological toxin and weapons charges.

A June 17 trial was scheduled for Roger Bergendorff, who has been in federal custody since his April 16 arrest. The charges carry a possible penalty of 30 years in prison and a $750,000 fine.

Authorities say about four grams of ``crude'' powdered ricin were found Feb. 28 in Bergendorff's extended-stay motel room several blocks off the Las Vegas Strip, along with illegal silencers for .22-calibre weapons.

Ricin can be lethal in amounts the size of the head of a pin. Federal prosecutor Gregory Damm has said he believes Bergendorff had enough of the substance to kill more than 500 people.

Bergendorff, 57, declined to speak with a reporter before his brief arraignment. His lawyer, Paul Riddle, declined to comment afterward. Bail was not discussed.

Authorities say the case doesn't have any ties to terrorism, but that Bergendorff admitted keeping ricin for protection against unspecified personal enemies. The unemployed graphic designer has said in court that he never would have used the substance.

His cousin, Thomas Tholen, 54, of Riverton, Utah, pleaded not guilty Tuesday in Salt Lake City to one felony count of knowing about a crime but failing to report it. Prosecutors say Tholen knew Bergendorff made ricin in Utah when he was staying with Tholen.

Bergendorff summoned an ambulance Feb. 14, complaining of breathing trouble, and was hospitalized for two months. For weeks he was unconscious in what police alternately described as a coma and sedation.

Authorities have said his symptoms were consistent with ricin exposure, although his lawyer denies that ricin made him sick. All traces of the substance are eliminated from the body within days, and ricin was not found in Bergendorff's motel room until two weeks after he went to the hospital. © 2008 The Canadian Press