A/HRC/12/48 (ADVANCE 1) page 8 phase of the military operations. The Mission also examined the practice of dropping lighter explosives on roofs (so-called roof knocking). It concludes that this technique is not effective as a warning and constitutes a form of attack against the civilians inhabiting the building. Finally, the Mission stresses that the fact that a warning was issued does not relieve commanders and their subordinates of taking all other feasible measures to distinguish between civilians and combatants. 38. The Mission also examined the precautions taken by the Israeli armed forces in the context of three specific attacks they launched. On 15 January 2009, the field office compound of the United Nations Relief and Works Agency for Palestine Refugees in the Near East (UNRWA) in Gaza City came under shelling with high explosive and white phosphorous munitions. The Mission notes that the attack was extremely dangerous, as the compound offered shelter to between 600 and 700 civilians and contained a huge fuel depot. The Israeli armed forces continued their attack over several hours despite having been fully alerted to the risks they created. The Mission concludes that the Israeli armed forces violated the requirement under customary international law to take all feasible precautions in the choice of means and method of attack with a view to avoiding and in any event minimizing incidental loss of civilian life, injury to civilians and damage to civilian objects. 39. The Mission also finds that, on the same day, the Israeli armed forces directly and intentionally attacked al-Quds hospital in Gaza City and the adjacent ambulance depot with white phosphorous shells. The attack caused fires which took a whole day to extinguish and caused panic among the sick and wounded who had to be evacuated. The Mission finds that no warning was given at any point of an imminent strike. On the basis of its investigation, the Mission rejects the allegation that fire was directed at the Israeli armed forces from within the hospital. 40. The Mission also examined the intense artillery attacks, again including white phosphorous munitions, on al-Wafa hospital in eastern Gaza City, a facility for patients receiving long-term care and suffering from particularly serious injuries. On the basis of the information gathered, the Mission found a violation of the prohibition of attacks on civilian hospitals in both cases. The Mission also highlights that the warnings given by leaflets and pre-recorded phone messages in the case of al-Wafa hospital demonstrate the complete ineffectiveness of certain kinds of routine and generic warnings. 6. Indiscriminate attacks by Israeli forces resulting in the loss of life and injury to civilians 41. The Mission examined the mortar shelling of al-Fakhura junction in Jabaliyah next to a UNRWA school, which, at the time, was sheltering more than 1,300 people (chap. X). The Israeli armed forces launched at least four mortar shells. One landed in the courtyard of a family home, killing 11 people assembled there. Three other shells landed on al-Fakhura Street, killing at least a further 24 people and injuring as many as 40. The Mission examined in detail statements by Israeli Government representatives alleging that the attack was launched in response to a mortar attack from an armed Palestinian group. While the Mission does not exclude that this may have been the case, it considers the credibility of Israel’s position damaged by the series of inconsistencies, contradictions and factual inaccuracies in the statements justifying the attack.