NEW YORK — Five people, including three young children, died in an apartment fire early Saturday, some taking refuge from the smoky blaze in a full bathtub and underneath a sink, fire officials said.

A 10-year-old boy was hospitalized in critical condition after the fire in a sixth-floor apartment in a public housing complex, Fire Department of New York spokesman Frank Gribbon said. The dead included a man, a woman and three girls between the ages of 15 months and 7, officials said.

Firefighters worked quickly, shattering windows and extinguishing flames about 45 minutes after the blaze began at 6:30 a.m. in Manhattan’s Chelsea neighborhood. The fire started in the kitchen, right by the apartment’s front door, fire officials said.

Fire officials said the adults tried to shelter their children in the bathroom and a back bedroom, probably after they were unable to get through the smoke.

Firefighters found the woman, a 3-year-old girl and a 15-month-old girl in the bathroom; the woman and one of the girls was in a full bathtub of water and the other was underneath the bathroom sink, Vuoso said.

The man was in a back bedroom with the two other children, officials said.

The cause was under investigation.

Kathy Creer, who lives one floor below, said she knocked on the family’s door after a neighbor told her about the blaze. She saw thick, black smoke coming from underneath the door.

“I was banging but I heard nothing, no noise,” Creer said. “It was so hazy that I couldn’t see anything.”

Creer said she kept pressing firefighters to find the children.

“I kept saying, ‘Where’s the babies? Where’s the babies?”’ she said.