A Brooklyn, New York, house fire that killed seven children ages 5 to 16 early Saturday burned, unnoticed, for some time in the first-floor kitchen before traveling upstairs to the bedrooms. The only smoke detector was in the basement.

The New York Times reported homes are supposed to have at least one fire alarm on every floor. But at the Sassoon family's house, "we believe there were none,” Fire Commissioner Daniel A. Nigro said, which is "always a tragedy in itself.”

The fire, which was started by a hot plate Orthodox Jewish mom Gayle Sassoon used to heat up food for her children during the Sabbath, was New York City's deadliest in eight years. Eliane, 16, David, 12, Rivkah, 11, Yeshua, 10, Moshe 8, Sara, 6, and Yaakob, 5, died from burns. Sassoon herself and her second-oldest daughter, Siphorah, 15, were hospitalized in critical condition. The father was away at the time of the fire.

“You can literally see what was a home for a large, strong family and now it’s wiped out, every room empty, burned and charred,” New York City Mayor Bill de Blasio said.

The building the family lived in was 90 years old and had not been outfitted with fire alarms upstairs. “They’re beautiful homes on this block, but God forbid you have a fire,” neighbor Robert Latish lamented to the Times. According to the National Fire Protection Association’s website, fire alarms typically halve the chances of casualties in a fire.

Fire department employees Saturday afternoon passed out fliers in the Sassoons’ neighborhood of Midwood to inform people they need to have or install multiple smoke detectors. “To hear a smoke detector two floors below is asking a lot,” Nigro told the Associated Press.