A Haarlem ship with a saw on the bow (in Dutch called the "zaagschip") was equipped with an iron saw fastened along the bow and front keel. This ship sawed through the Damietta harbour chain and allowed the fleet to attack the city, which was a success. The Damietta story is however contradicted by the eyewitness account of Oliver of Cologne, who led the Dutch fleet, and who never mentioned the heroic actions of the Haarlem knights.