Updated 02/13/12 – 6:27 a.m.

CHICAGO (CBS) – In what the Fire Department calls a rare occurrence, firefighters missed a young boy after three searches of a burning home in the Roseland neighborhood.

As WBBM Newsradio’s Steve Miller reports, investigators will now try to find out how a 7-year-old boy was missed on Saturday in the home in the 10700 block of South Prairie Avenue.

LISTEN: WBBM Newsradio’s Steve Miller reports

The lifeless body Omariontae Tucker, 7, was found in an attic crawlspace, next to the body of a dog. The Cook County Medical Examiner’s office says the boy died from carbon monoxide intoxication caused by smoke inhalation.

Earlier, crews had rescued a 61-year-old woman from the home, but were unaware of the boy in the attic. She also later died.

Omariontae was found in the crawl space of an unfinished attic in home, Fire Media Affairs Chief Kevin MacGregor said.

“He was all the way up in the eaves, right along the gutter line near the window,” MacGregor said. “Maybe he was trying to find a way out. It certainly was an unusual position to find the little guy, very unfortunate.”

Fire Media Affairs Director Larry Langford says firefighters did a primary search of the home, then a secondary search, then a final search – and did not find Omariontae.

Langford says at that point, the Fire Department heard that the boy might still be in the building.

And so, at least two hours after firefighters’ final search, when a crew from the Office of Fire Investigations went in to determine origin and cause, they found the body.

“It is a rare occurrence that somebody gets missed on a search,” Langford said.

Firefighters also removed another dog from the house, but were unable to revive the animal.

Omariontae lived with his mother and grandmother in the home, relatives said. The rescued woman, Barbara Scott, was his grandmother, they said.

Paramedics initially took the woman to Roseland Community Hospital, but she was later transferred to Loyola University Medical Center in Maywood, the fire department said. Scott, of the 1400 block of East 74th Street, was pronounced dead at the hospital at 5:11 p.m. Sunday, the Medical Examiner’s office said.

The fire started in the basement and raced up the exterior walls, officials said. The cause is under investigation.

Firefighters responded to the blaze at about 9:45 a.m. Saturday, searched the house and rescued Scott on the first floor.

At about 1 p.m., investigators at the scene were notified someone else might be in the house, a police spokesman said. Office of Fire Investigations officials found the boy, MacGregor said.

Omariontae’s family said he was a lively second-grader who attended a charter school.

He loved to walk Coleman’s mother’s dog, a Shih Tzu.

“He was a good kid, into his video games,” an uncle, Oliver Coleman. “We’re having a very hard time with this.”

On Saturday night, a group of Omariontae’s relatives gathered outside the 1 1/2-story home as workers boarded up its broken windows.

“They overlooked him, they missed him,” Coleman said, his voice cracking with emotion.

The family members stood in a prayer circle around a candle and red balloons, quietly remembering the boy.

Then one of them wailed: “He didn’t have to go this way!”

The Chicago Sun-Times contributed to this report, via the Sun-Times Media Wire.

© Sun-Times Media Wire Chicago Sun-Times 2012. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.

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