Flavius Josephus, The Wars of the Jews
William Whiston, A.M., Ed.

[425] Now the next day was the festival of Xylophory; upon which the custom was for every one to bring wood for the altar (that there might never be a want of fuel for that fire which was unquenchable and always burning). Upon that day they excluded the opposite party from the observation of this part of religion. And when they had joined to themselves many of the Sicarii, who crowded in among the weaker people, (that was the name for such robbers as had under their bosoms swords called Sicae,) they grew bolder, and carried their undertaking further; insomuch that the king's soldiers were overpowered by their multitude and boldness; and so they gave way, and were driven out of the upper city by force. The others then set fire to the house of Ananias the high priest, and to the palaces of Agrippa and Bernice; after which they carried the fire to the place where the archives were reposited, and made haste to burn the contracts belonging to their creditors, and thereby to dissolve their obligations for paying their debts; and this was done in order to gain the multitude of those who had been debtors, and that they might persuade the poorer sort to join in their insurrection with safety against the more wealthy; so the keepers of the records fled away, and the rest set fire to them. And when they had thus burnt down the nerves of the city, they fell upon their enemies; at which time some of the men of power, and of the high priests, went into the vaults under ground, and concealed themselves, while others fled with the king's soldiers to the upper palace, and shut the gates immediately; among whom were Ananias the high priest, and the ambassadors that had been sent to Agrippa. And now the seditious were contented with the victory they had gotten, and the buildings they had burnt down, and proceeded no further.