DES PLAINES (CBS) — A mother and four daughters — the oldest only 6 years old — died in a house fire Wednesday morning in Des Plaines, officials said.

Five people were killed in a Des Plaines house fire. (CBS)

The home is located in the 700 block of Oakton Street. The four sisters and their mother were found on the second floor of the two story residence, Fire Chief Dan Anderson said. The girls ranged in age from one year to six.

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The mother is identified as 25-year-old Citahaly Zamiodo. The girls are identified as Renata P. Espinosa, 6; Genesis A. Espinosa, 5; Allizon V. Espinosa, 3; and Grace Espinosa, 1.

When firefighters arrived, they encountered flames and heavy smoke coming from the second floor. Firefighters began to fight the fire and attempted to rescue the people inside, Anderson said. The four children were taken to local hospitals where they were pronounced dead.  Their mother was pronounced dead at the scene.

“In my 30-plus years of fire service, this is the most difficult scene I’ve responded to. Any loss is tragic, but losing four young children is truly heartbreaking for our department and the entire community,” Anderson said.

As CBS 2’s Charlie De Mar reported, a relative says the family is struggling to believe the loss. Neighbors were likewise in shock.

“I saw the children,” said neighbor Sam Kuraishi. “I think somebody took them in an ambulance.”

“I smelled faintly something like plastic burning,” said Pabel Marreno, who lives on the first floor of the now-burned-out building. “There was too much smoke.”

Marreno said he was alerted to the fire by someone passing by who saw the smoke.

“And he’s like: ‘You’ve got to come out. Your house is on fire,’” Marreno said.

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Marreno said at first, firefighters struggled to get in. They had trouble getting through the locked front door

He watched as firefighters carried the bodies one by one.

“All of the sudden, one fireman comes out carrying one of the kids. There were four kids up there,” Marreno said. “Mom and the baby are not coming out. Mom and the baby are not coming out.”

Neighbors say that the father of the kids was at work when the fire started.

One firefighter injured his knee. The fire, which was contained to the home, is under investigation, Anderson said.

“This is a very sad day for the City of Des Plaines. This kind of tragedy touches the heart of every Des Plaines resident. The City and the Des Plaines community grieve with this family and offer our support in any way we can,” said Des Plaines Mayor Matt Bogusz.

Crime scene tape remained up around the duplex house and windows were boarded up late Wednesday.

The family said they have a lot of questions surrounding the circumstances of the fire, and were waiting to hear much more from investigators.

The family also has set up a GoFundMe page to help pay for memorial expenses.

CBS 2’s Steven Graves and Charlie De Mar contributed to this report.

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