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DES PLAINES, Ill. — Officials said they have an idea on what started a fire in the suburbs that left a mother and her four young girls dead.

The Des Plaines Fire Department on Thursday said they’re investigating whether the fire started from a space heater on the second floor of the duplex building on the 700 block of West Oakton Street.

Fire investigators believe findings show that the fire originated at the top of the stairs into the second-floor unit, the only entry and exit to the unit. Based on the location of the fire, it likely prevented the family from being able to escape.

The fire started around 10:30 a.m. Wednesday. Citahaly Zamiodo, 25, and her four daughters — Renata Espinosa, 6, Genesis Espinosa, 5, Allison Espinosa, 3, and 1-year-old Grace Espinosa — were all killed in the fire.

The girls were all transported to area hospitals, where they were pronounced dead. Their mother was pronounced dead at the scene.

“I’ve been doing this for 30-some-odd years, and this is the worst day I’ve ever had,” Des Plaines Fire Chief Daniel Anderson said during a press conference.

A massive amount of emergency crews responded to the scene, including fire departments from Niles and Northbrook.

After the fire was out, the home was left with broken windows and smoke-stained siding next to the white snow.

Next door neighbor Sam Kuraishi said the man who lived in the residence was a landscaper who called him with an urgent question.

“‘There is a fire at my house, are my children there?,’” the neighbor said the man asked him.

Pabel Marrero said he was in the apartment just below the family’s when the fire started. Marrero said someone pounded on his door.

“He’s screaming at me to come out ‘the house, the house is on fire’” he said.

A GoFundMe campaign has been created to help the family with burial expenses and other costs.

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