The first sign of trouble came around 3 a.m. Sunday when Shabbir Ahmed's sister-in-law woke up feeling ill.
"It started from there," Ahmed said. "She was feeling dizzy."
Four hours later his 77-year-old mother, Rasheeda Akhter, was so ill she could not get out of bed. "They took her to Swedish Covenant Hospital but before she got there, she died," Ahmed said.
An hour later, relatives tried to wake his 18-year-old niece Zanib Ahmed. "She couldn't wake up," Ahmed said. She was rushed by ambulance to the same hospital where "they tried their best to save her life but she did not come back."
Ahmed's brother then gathered five children ranging in age from 5 to 12 and took them to a hospital for observation. "We figured out something was wrong," said Ahmed, 49. "They were OK, they were eating and playing around."
Autopsies for Akhter and her granddaughter are scheduled for today, but officials suspect they were overcome by carbon monoxide.
Fire officials and workers from Peoples Gas have determined there was a leak in the exhaust system of the boiler in the basement of the four-flat in the 2500 block of West North Shore Avenue. Fire Department spokesman Larry Langford said officials believe people in the building had been exposed to low levels of carbon monoxide over a long period of time.
When fire officials first responded to the address, they checked the carbon monoxide levels and found no indication of a leak in the building, according to Fire Department spokeswoman Meg Ahlheim said.
When paramedics were called back to the scene, they checked again and still found no evidence of a leak, Ahlheim said. A carbon monoxide detector in a room near the boiler had not gone off, according to Langford, but high levels were found in the boiler room.
Langford said the building had no other working carbon monoxide detectors, though there were smoke detectors. City code requires carbon monoxide detectors on every floor where there are bedrooms, Langford said.
Ahmed said no work was done recently on the boiler. "It was the same boiler we had, it was working perfectly, then all of a sudden like a car, cars break down," he said.
The four-flat building is owned by his family and was purchased by his father more than 20 years ago. He said relatives live in each of the units. "We owned the whole building, nobody else was living there."
Ahmed said his parents came to the United States from Pakistan. His father died about two years ago from a heart condition. He said his mother had three sons and a daughter and 11 grandchildren.
He called his mother a "beautiful person." He said the grandchildren would call her "Dadyji," which is Urdu for grandmother. He said most of the grandchildren lived in the building and she was a constant presence in their lives.
"All of the kids loved her and played with her all of the time, they are going to miss her very badly," Ahmed said.
He said his niece was a senior at St. Scholastica Academy High School and was scheduled to graduate this year. She was considering going to Northwestern University, where she wanted to go into premed.
"She had planned to go to medical school, she always talked about being a surgeon," Ahmed said.
She was the oldest of three children, and leaves behind a sister and brother, Ahmed said. "They were very close."
Another relatives said the family "is going through a tough time, they were very good people."
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