Von Bergendorff' title='Roger Von Bergendorff' class='tpstyle'>Roger Von Bergendorff, 57, is charged with possession of a biological toxin, and two firearms-related charges, the Department of Justice said in a release.

"It is illegal under federal law to knowingly possess a biological agent and toxin of a type and quantity that is not reasonably justified by a prophylactic, protective, bona fide research, or other peaceful purpose," said Gregory A. Brower, U.S. Attorney for Nevada.

Von Bergendorff, while a resident at an Extended Stay America Hotel in Las Vegas, contacted emergency medical personnel and advised he had problems breathing and was hospitalized.

A police investigation found, among other things, a cache of weapons and instructions to prepare ricin. Law enforcement officials also searched Salt Lake City storage lockers rented by Von Bergendorff, where they found castor beans, chemicals used in the production of ricin, a respirator, filters, painter's mask, laboratory glassware, syringes, and a notebook on ricin production.

Ricin is a toxin made from the mash remaining after castor beans are processed for oil.