Boko Haram's continuing raids of terror have turned a swath of territory in the Sahel region in northern Africa into a virtual wasteland, barren of crops and livestock, pocked by ghost villages lying in ruin. Add to this desolation an early "lean season" — the precarious time between harvests when temperatures soar, rainfall is scant, and hunger, even in good years, is a threat to the area's subsistence farmers and herdsmen — and the stage is set for starvation on a mass scale.

The United Nations says that more than 50,000 people in northern Nigeria are in imminent danger of starvation, cut off from help in areas where it is too dangerous for aid workers to travel and that some 1.4 million people in the region lack sufficient food supplies.

Boko Haram, an extremist group whose name roughly means "Western education is a sin," has killed more than 20,000 people and caused more than 2.5 million people to flee their homes. President Muhammadu Buhari of Nigeria was elected a year ago largely on a promise to defeat Boko Haram.

The Nigerian Army and coalition forces from Niger, Chad and Cameroon — with the help of foreign advisers, including Americans — have successfully wrested some territory from Boko Haram in Nigeria and cut off its supply routes.

Villages that have been emptied of Boko Haram have seen raids by desperate fighters forced to come out of the surrounding countryside in search of food. The hunt for food is also forcing Boko Haram into northern Cameroon, where attacks have become more common. More than 70 percent of farmers there have abandoned their land, and many herdsmen can no longer get their cattle to market.

This dire situation will only get worse unless action is taken now to avert future hunger. United Nations agencies providing vital assistance in the region are woefully underfinanced, and they urgently need help from national and individual donors.

Getting emergency food aid to the 50,000 people in immediate danger of starvation must be a priority for Nigerian and coalition forces. Tens of thousands of civilians cannot be allowed to die in the effort to starve out Boko Haram.

FROM AN EDITORIAL IN THE NEW YORK TIMES