Officials said arson is suspected in the destruction at the Hanichei HaYeshivot study hall.
Investigators discovered that a flammable liquid had been poured on items at three separate locations within the building, and then ignited.
A student who studies at the yeshiva raced into the building when he saw the flames, according to a witness. He helped fight the blaze until firefighters arrived, but was unhurt.
There were no injuries. Authorities have opened an investigation.