LAS VEGAS -- In a news conference Friday afternoon, federal officials said the powder found in an Extended Stay America hotel was ricin. They said they will launch a full investigation into the poison's creation and how it was brought to Las Vegas.

A man turned a plastic bag containing a vial of the poison over to hotel workers around 3 p.m. Thursday. After turning it over to authorities, the hotel quarantined three rooms, witnesses said, and the local and federal authorities started a preliminary examination.

Police said the man who was renting the room where the poison was found is in critical condition. They would not say if he is a victim of an attack or if he was the ricin's manufacturer, but he had been staying in the hotel before he went to the hospital on Feb. 14 complaining of respiratory issues.

After being in the hospital for a week, the hotel contacted the man's family for room payment, investigators said. It was one of the critical man's friends or relatives who found the poison in the room -- along with some castor beans -- and turned it over to the authorities after trying to claim the man's belongings.

Agents do not think foul play is involved and the FBI said the case doesn't appear to be terrorism-related. While they say the poison is not a health threat to the population, authorities aren't sure why the vial of ricin was in the room and have started a full investigation into its creation and who brought it to Las Vegas.

Ricin can be deadly if ingested, inhaled or injected into the body. Authorities said that two-tenths of a milligram is enough to kill a person. It has been used in some cancer research, but it has also been used in assassinations and turned up in the homes of suspected terrorists.