A/HRC/12/48 (ADVANCE 1) page 7 Palestinian armed groups and thus combatants. It concludes, however, that the attacks against the police facilities on the first day of the armed operations failed to strike an acceptable balance between the direct military advantage anticipated (i.e. the killing of those policemen who may have been members of Palestinian armed groups) and the loss of civilian life (i.e. the other policemen killed and members of the public who would inevitably have been present or in the vicinity), and therefore violated international humanitarian law. 4. Obligation on Palestinian armed groups in Gaza to take feasible precautions to protect the civilian population and civilian objects 35. The Mission examined whether and to what extent the Palestinian armed groups violated their obligation to exercise care and take all feasible precautions to protect the civilian population in Gaza from the inherent dangers of the military operations (chap. VIII). The Mission was faced with a certain reluctance by the persons it interviewed in Gaza to discuss the activities of the armed groups. On the basis of the information gathered, the Mission found that Palestinian armed groups were present in urban areas during the military operations and launched rockets from urban areas. It may be that the Palestinian combatants did not at all times adequately distinguish themselves from the civilian population. The Mission found no evidence, however, to suggest that Palestinian armed groups either directed civilians to areas where attacks were being launched or that they forced civilians to remain within the vicinity of the attacks. 36. Although the incidents investigated by the Mission did not establish the use of mosques for military purposes or to shield military activities, it cannot exclude that this might have occurred in other cases. The Mission did not find any evidence to support the allegations that hospital facilities were used by the Gaza authorities or by Palestinian armed groups to shield military activities or that ambulances were used to transport combatants or for other military purposes. On the basis of its own investigations and the statements by United Nations officials, the Mission excludes that Palestinian armed groups engaged in combat activities from United Nations facilities that were used as shelters during the military operations. The Mission cannot, however, discount the possibility that Palestinian armed groups were active in the vicinity of such United Nations facilities and hospitals. While the conduct of hostilities in built-up areas does not, of itself, constitute a violation of international law, Palestinian armed groups, where they launched attacks close to civilian or protected buildings, unnecessarily exposed the civilian population of Gaza to danger. 5. Obligation on Israel to take feasible precautions to protect the civilian population and civilian objects in Gaza 37. The Mission examined how the Israeli armed forces discharged their obligation to take all feasible precautions to protect the civilian population of Gaza, including particularly the obligation to give effective advance warning of attacks (chap. IX). The Mission acknowledges the significant efforts made by Israel to issue warnings through telephone calls, leaflets and radio broadcasts, and accepts that in some cases, particularly when the warnings were sufficiently specific, they encouraged residents to leave an area and get out of harm’s way. However, the Mission also notes factors that significantly undermined the effectiveness of the warnings issued. These include the lack of specificity and thus credibility of many pre-recorded phone messages and leaflets. The credibility of instructions to move to city centres for safety was also diminished by the fact that the city centres themselves had been the subject of intense attacks during the air