CHICAGO (WLS) — The search for a missing person continues after a deadly apartment fire in the Austin neighborhood Thursday.

The fire that left three people dead is being investigated for possible arson, although it’s still unclear what exactly sparked the fire.

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The fire in the apartment building in the 5200-block of West North Avenue also left three others injured.

According to Chicago police, the victims who lost their lives were a five-year-old boy, a 32-year-old woman, and a 76-year-old man. Among the injured was a four-year-old boy, though their identities have not yet been released.

Some people who live in the neighborhood reported hearing gunshots before seeing the fire.

Thirty-Seventh Ward Alderman Emma Mitts said she’s been told the fire is the result of a domestic dispute between two men.

Thursday, ATF agents were at the scene helping with the investigation.

Heavy machinery was used to demolish the remains of a burnt apartment building, allowing rescue teams to look for any remaining individuals who might still be inside.

Andrea Boyd is hoping crews might find her loved one in the burnt wreckage.

“I’m just waiting on the detectives to see if she’s in there,” Boyd said. “They told me to give them a moment to check.”

Authorities have not officially released the cause of the fire.

The Red Cross said the massive blaze displaced over two dozen people.