Eight workers and a guest at the Westin Baltimore Washington International Airport were taken to the hospital to be treated for carbon monoxide poisoning Sunday afternoon, Anne Arundel County fire officials said.

Authorities said they found high levels of carbon monoxide in the hotel after a paramedic was called there to treat an employee in the laundry area of the building who felt weak.

Fire officials evacuated all seven levels of the hotel, at 1110 Old Elkridge Landing Road in Linthicum Heights, Fire Department Lt. Russ Davis said.

While treating that patient, a carbon monoxide alarm went off, indicating high levels of carbon monoxide in the building.

Davis said four people, all hotel workers, were transported to the Shock Trauma Center at the University of Maryland Medical Center. Five other people were taken to local hospitals. All were in stable condition, Davis said.

It is unclear how many guests were at the hotel, but fire officials say hotel management said 64 rooms were occupied at the time.

Fire officials shut down all combustion appliances and ventilated the building. Davis said the hotel remains empty while authorities determine the source of the carbon monoxide leak.