A carbon monoxide leak at a Falls Church apartment complex sent three people to the hospital and temporarily displaced dozens of residents early Wednesday morning.

Fire and rescue officials in Fairfax County said emergency crews responded to Barcroft Plaza Apartments, in the 3600 block of Malibu Circle, around 2:30 a.m. after a resident reported feeling nauseated and dizzy.

Tests determined that carbon monoxide levels in the complex were extremely high and three people were taken to a local hospital, officials said. It was unclear if all three people lived in the same unit. Officials did not release their ages or genders.

The building was evacuated until the source of the leak was located. Residents are now being allowed to return to their units.

Officials said the hospitalized victims were initially in life-threatening condition, but all three are now expected to fully recover.

Carbon monoxide is a colorless, odorless, tasteless gas that can be toxic when inhaled. Symptoms of carbon monoxide poisoning include headache, nausea and dizziness.

Carbon monoxide poisoning can result in death. Anyone who suspects they might have carbon monoxide poisoning should seek immediate medical attention.