SUFFOLK, Va. (WAVY) — Two children were pulled from a house fire by Suffolk firefighters and police Wednesday afternoon on Smith Street.

The children were taken to Children’s Hospital of The King’s Daughters. In an update, fire officials said one of the two children is 3 years old and remained in critical condition as of Wednesday night. The other child, an older sibling, was being monitored overnight for smoke inhalation.

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Three firefighters were also taken to a local hospital to be treated for heat exhaustion. One has since been released, officials said.

“These conditions yesterday, we were in the mid-80s and we had a pretty good fire that was going on, so you had heat from the incident itself, with all the equipment and things, certainly [firefighters] are in very good physical shape, but those conditions could lead to the situations we saw,” said Tim Kelley, Suffolk’s media and communications director.

The fire broke out around 1:20 p.m. on Smith Street at St. James Avenue, just west of the downtown area. It was eventually upgraded to a three-alarm fire, with eight engines and other units responding.

Ginger Rouse, who lives next door, watched the fire unfold from inside her home.

“I saw huge flames coming from the apartments,” Rouse said. “It seemed like it was coming from the stairs, it seemed like the whole back was on fire.”

Photos from Suffolk Fire & Rescue show firefighters on a ladder going into an upper-level window after they said no one was found in an initial search.

The children were found in a primary search, officials clarified, and no one else was found in a completed secondary search. The fire however was marked under control at 3:15 p.m., firefighters said.

The American Red Cross was working with the 11 people — five adults and six children — that were displaced from four apartments.

The cause of the fire is still under investigation. Fire Marshal Chris Cornwell said that those home at the time of the fire were alerted by a working smoke detector in the building.

Officials with the Suffolk Police, Suffolk Fire Marshal’s Office and Child Protective Services are investigating the fire.

10 On Your Side is working to learn more.