The trickle of food aid Israel allows to enter Gaza after nearly 22 months of war is seized by Palestinians risking their lives under fire, looted by gangs or diverted in chaotic circumstances rather than reaching those most in need, UN agencies, aid groups and analysts say.- 'Darwinian experiment' - Some of the aid is looted by gangs -- who often directly attack warehouses -- and diverted to traders who resell it at exorbitant prices, according to several humanitarian sources and experts.