A man who may have been exposed to toxic ricin in his Las Vegas motel room has regained consciousness and is speaking with investigators, authorities said Friday.

Officials said Roger Bergendorff, 57, remained in critical condition at a Las Vegas hospital.

An FBI agent in Las Vegas told The Associated Press that investigators are speaking with Bergendorff for the first time since he was hospitalized on Valentine's Day and several vials of ricin powder were later found in his motel room.

"We are in the process of speaking with him," said Special Agent David Staretz, spokesman for the FBI office in Las Vegas.

Authorities hope Bergendorff can provide information about the Feb. 28 discovery of the deadly powder, along with castor beans from which it is derived, at an extended stay motel where he had been living several blocks off the Las Vegas Strip.

Officials insist they've found no contamination anywhere, and no link to terrorism. But they consider ricin a "biological weapon," and are trying to determine where it came from.

Authorities suspect Bergendorff was exposed to ricin, and experts have said his symptoms appeared consistent with ricin exposure. But no one said they could be sure, because the poison breaks down in the body within days and Bergendorff was hospitalized for two weeks before the ricin was discovered at the motel.

A younger brother, Erich Bergendorff of Escondido, Calif., said Roger Bergendorff was moved Wednesday from intensive to intermediate care in the critical ward of Spring Valley Hospital Medical Center in Las Vegas.

Erich Bergendorff said his brother was receiving dialysis for failing kidneys, and might still be on a ventilator to help him breathe.

Hospital spokeswoman Naomi Jones said Friday that Bergendorff remained in critical condition.

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