Police in Las Vegas, Nevada, are investigating the discovery of the deadly poison ricin in a hotel room Thursday.

Authorities were called to an Extended Stay America hotel around 3 p.m. after a man brought a bag holding a small container to the manager's office. The man said he found it while retrieving items from a hotel room.

It's "100 percent ricin," said Capt. Joe Lombardo of the Las Vegas Metropolitan Police Department. "We don't know who (the ricin) belongs to or why it would be here at this time."

Three hotel employees and a fourth person who came to the room to retrieve some items were taken to the hospital as a precaution, Officer Ramon Dendy told CNN. Three police officers who went into the room are also being watched at the hospital. None of the seven have shown symptoms of ricin poisoning, which can include anything from difficulty breathing, fever, cough, nausea and sweating to severe vomiting and dehydration.

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"We did have enough ricin to be of concern," Lombardo said. "At this point, it has been contained and processed where it's not a threat to anybody." Watch police discuss ricin discovery »

Lombardo said the "area of concern" is under quarantine and is going through a decontamination process. All seven people have been decontaminated.

Police said they don't know how many people have stayed in the room recently.

The discovery of ricin alarms law-enforcement agencies because authorities in several countries have investigated links between suspect extremists and ricin.

Full article here.