Deadly ricin package found in US hotel

Seven people have been taken to hospital after the deadly toxin ricin was found in a Las Vegas motel.

It was in a package a guest took to the hotel manager after finding it in his suite.

Ricin is extremely lethal - an amount the size of a pinhead can kill a human.

The manager was suspicious of the contents, thinking them some type of drug, and called police to the Extended Stay America Motel.

Two preliminary tests indicate it contained ricin, which is made from the waste products of processed beans from the castor oil plant.

"Ricin has no medical uses other than cancer research," police Captain Joseph Lombardo said.

"An individual citizen other than being involved in cancer research or cancer prevention would not have any legal means or proper means of having that."

Investigators did not immediately believe the substance was intended for an attack.

"This is not a terror incident at this point," Mr Lombardo said.

Police cordoned off the area and isolated the room where the ricin was found.

Three motel employees and another person were quarantined and decontaminated at the site, then taken to hospitals for further testing. All appeared to be well. Three police officers who had been exposed were also taken to hospital.

It takes between six and eight hours for someone exposed to ricin to show signs of contamination.

Homeland Security officials joined local police in the investigation. Officials from the FBI, Las Vegas Health District, a hazardous materials team and the National Guard were also at the scene.