Mistaking the al-Aqsa mosque for the Temple of Solomon, Raymond of Aguilers wrote a notorious account of what he had observed-
“Wonderful sights were to be seen. Some of our men (and this was more merciful) cut off the heads of their enemies; others shot them with arrows, so that they fell from the towers; others tortured them longer by casting them into the flames. Piles of heads, hands and feet were to be seen in the streets of the city.”
Source- Sinclair, Andrew. Jerusalem- The Endless Crusade. New York- Crown Publishers, 1995, p. 55-56.