A fast-moving fire blazed through a home as families celebrated a Jewish holiday, killing an 8-year-old boy and injuring five other children.

Officials said the flames started shortly after 9:30 p.m. Wednesday at the building in the Midwood section of Brooklyn. The children, ranging from 1 to 10 years old, were inside the house while a number of other people were outside at a dinner marking the end of the holiday Sukkot.

The cause of the blaze is unknown.

Witnesses told the Daily News that the children's parents heard their cries for help and went back into the house to get them, but were unable to reach the 8-year-old trapped in a top-floor bedroom, whom officials identified as Avigdor Krasny. He was pronounced dead upon arrival at Coney Island Hospital.

A 1-year-old girl was in critical condition at Staten Island North Hospital. Four other children — a 3-year-old boy, a 5-year-old girl, a 7-year-old boy and a 10-year-old boy — were in stable condition at that facility.

"The children were screaming," Rebecca Liss told the Daily News. "The parents heard them, but it was too late."

Witnesses said firefighters tried to get to Krasny as well.

"They broke the glass and cut the gate," David Cohen told The New York Times.

New York City Fire Department Deputy Chief Michael Marrone told NY1 that the design of the house made it difficult.

"A good amount of fire up there, and if you notice the peak of the roof there, it's an attic space. It's very tight quarters," Marrone said. "It's tough to make a quick push up there, but we got in there as soon as we could."

The fire was declared under control around 11 p.m. and four firefighters suffered minor injuries.