Firefighters investigate a blaze that killed a young child Wednesday in Montgomery Village. (Dan Morse/The Washington Post)

A 4-year-old boy died in a fire at a Montgomery Village apartment complex Wednesday afternoon, and four other people were taken to hospitals for treatment, Montgomery County fire officials said.

Firefighters arrived about 4 p.m., said Beth Anne Nesselt, a spokeswoman for the county’s Fire and Rescue Service. They found heavy fire and smoke on the second floor that extended to the top floor of the three-story building, according to a statement Wednesday night.

More than 80 firefighters were sent to the blaze at the Cider Mill Apartments in the 18200 block of Lost Knife Circle. It was declared under control by 4:25 p.m., Nesselt said.

One man trapped on a third-floor balcony was rescued by firefighters who used ladders to reach him, authorities said. The man suffered serious injuries that were potentially life-threatening. Officials said a second man was treated for smoke inhalation. His condition was not immediately available.

Two children were taken to a hospital with injuries that were not considered life-threatening.

Authorities did not immediately identify the child who was killed.

Firefighters examined the scene into the evening, focusing much of their attention on a second-story apartment that was gutted by the blaze. Two apartments above it were heavily damaged. Officials said it was too early to determine what sparked the fire, but they said it appeared to be accidental.

Twelve apartments were damaged, some directly by the fire and some by smoke or water, authorities said, and about 40 residents were displaced. Firefighters and Red Cross workers were on the scene, working to place people in hotels or with friends.

One resident, a 23-year-old man who works as a finance manager, said he was at work at the time of the fire.

“I feel terrible for the parents” of the child, the man said. He said fire officials told him that his apartment, on the third floor, had been destroyed.

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