Why did starvation become a major humanitarian crisis during the Nigerian Civil War?

During the Nigerian Civil War, starvation emerged as a severe humanitarian crisis primarily because the secessionist state of Biafra was systematically isolated as the conflict progressed.12

As federal forces pressed Biafra's boundaries inward from the north, west, and south, the region shrank to a fraction of its original size. By 1968, Biafra had lost its seaports, effectively becoming landlocked and cutting off traditional supply routes. With the territory surrounded and its infrastructure destroyed, the population became entirely dependent on limited supplies brought in by air. This blockade, combined with the intensity of the military conflict, prevented adequate food and medical resources from reaching civilians, leading to a catastrophic mortality rate estimated between 500,000 and 3,000,000 people. In response to the dire conditions, international organizations and various countries eventually organized airlifts to provide emergency aid to the starving population.123