LAS VEGAS -- Following the discovery of a deadly poison in a Las Vegas hotel room, Metro police said they have confirmed the safety of the city.

Officials investigated all known locations where any person involved in the ricin investigation visited or stayed. Those locations include the Extended Stay America motels on Valley View Boulevard and Boulder Highway, as well as the Excalibur Hotel-Casino.

Authorities said there is no indication that ricin was at any other locations.

As far as the man who was renting the room where the ricin was found, hospital officials said Roger Von Bergendorff is still in critical condition.