AKRON, Ohio (WJW) – One person has died following a carbon monoxide leak at an Ohio apartment complex in which pet birds alerted firefighters to the danger.

Officials with Summit County confirm the county medical examiner’s office is investigating the death of a 66-year-old woman as possibly related to carbon monoxide. The woman was discovered in the bathroom within the Akron apartment complex and was pronounced dead at the scene just after midnight.

Akron firefighters had been called to the Timber Top Apartments & Townhomes on Rocky Brook Drive just before 10 p.m. Thursday for a medical emergency.

It didn’t take long for one firefighter to realize they had a bigger problem: carbon monoxide.

As firefighters checked on a 23-year-old man, they said he couldn’t give direct answers to their questions and expressed worry about his birds.

“He was real nervous about them,” Lt. Tim Morrison of the Akron Fire Department said. “He had like eight or nine birds in his house and what happened was one of the lieutenants walked over to the birds’ cage, and just to say, ‘Oh, everything’s fine,’ and he looked in and he saw four dead birds on the bottom of the cage.”

The firefighter asked the man’s parents how they were feeling and they couldn’t give him a straight answer. That’s when he knew there was a problem.

A carbon monoxide check found high levels of the odorless, colorless gas in the apartment.

Morrison said they ended up evacuating about 20 apartments after high levels of carbon monoxide were found in other units as well.

Morrison said firefighters had to “bust down” the door of one of those apartments. Inside they found two young children and two adults who were both unconscious.

“It was a great save,” Morrison said.

Morrison said 10 people were transported to local hospitals. The identities of the patients and their conditions were not available early Friday morning.

“It’s pretty amazing Lt. [Cameron] Mack was able to put things together and realize that something wasn’t right,” Morrison said.

“If he wasn’t smart enough to put those things together,” Morrison said. “We’d had a much worse situation going on.”

Once firefighters ventilated the affected apartments, police officers were able to escort other residents to their apartments to retrieve medications and other important belongings. The American Red Cross was assisting the evacuees with a place to stay until their apartments were safe to return to.

“This shows you how important having a carbon monoxide detector is, how important it is, to have that kind of detector in your home,” Morrison said. He also said everyone should have a smoke detector.

According to the Centers for Disease Control and Prevention, every year more than 4,000 people are hospitalized due to carbon monoxide poisoning.

The symptoms can come on quickly, and appear flu-like with headache, dizziness, upset stomach and vomiting. Chest pains and confusion can also be part of the mix. Symptoms can also creep up on victims when they’re asleep or intoxicated, putting them in serious danger before they know it.

While thousands are hospitalized every year for carbon monoxide poisoning, roughly 50,000 will visit the emergency room because of it. An estimated 430 people die from the hazard every year.