United Nations, Ramadan 18, 1435, Jul 15, 2014, SPA -- The U.N. aid agency for Palestinians on Tuesday described the damage from Israel's ongoing air offensive on the Gaza Strip as "immense," with more than 500 homes destroyed, and aid agencies warned of a major water crisis within days as airstrikes have destroyed the water and sewage system. "The level of human losses and destruction in Gaza is really immense," U.N. Relief and Works Agency for Palestine refugees (UNRWA) spokesman Sami Mshasha said in Geneva. "According to our latest figure, we are talking about 174 killed and well over 1,100 injured." "This number will increase. The numbers are increasing by hours," Mshasha told reporters. "A good number of those killed and injured are women and children. That is a cause of concern for UNRWA." The spokesman said 560 homes had been totally destroyed, while thousands of buildings-including 47 UNRWA facilities-had suffered damage from bombings. Meanwhile, the International Committee of the Red Cross (ICRC) said hundreds of thousands of Gazans are without water, and the situation is sure to worsen. "Within days, the entire population of the [Gaza] Strip may be desperately short of water," Jacques de Maio, the chief of the ICRC delegation in Israel and the occupied territories, said in a statement from Geneva. If hostilities continue, as temperatures soar in the region, "the question is not if but when an already beleaguered population will face an acute water crisis," de Maio said. "Water is becoming contaminated and sewage is overflowing, bringing a serious risk of disease." --SPA 23:27 LOCAL TIME 20:27 GMT www.spa.gov.sa/w