Washington, DC — Fire officials said a woman is dead after being exposed to carbon monoxide on Sunday morning.

D.C. Fire and EMS were called just before 9:45 a.m. to the 100 block of Kenilworth Avenue in Northeast for a medical emergency.

Once on scene, first responders activated their carbon monoxide devices and found that there was high levels of carbon monoxide in the apartment. An unconscious woman was then found and and taken out of the home.

The woman was later pronounced dead at the scene. She has not yet been identified.

The cause of the leak was the stove was left on inside the woman’s apartment, fire officials said. A fire spokesperson said the woman did not have a carbon monoxide detector.

The 12-unit apartment building was evacuated and ventilated before officials found the leak was confined to that single apartment.

All residents have since been let back into the building.

D.C. Fire and EMS spokesman Vito Maggiolo said it is important for people to know the signs of carbon monoxide poisoning and what to do if they feel they have been affected. If you start to feel a headache, nausea, breathlessness, collapse or feel dizzy, you should leave the area and contact the fire department.

Exposure to carbon monoxide could lead to loss of consciousness and even death.