UNITED NATIONS — International donors pledged over $160 million for life-saving support for millions of people in west Africa whose lives have been thrown into turmoil by the Muslim extremist group Boko Haram on Friday — but that’s just one-third of the amount needed for the rest of this year.

U.N. Deputy Secretary-General Jan Eliasson called the upheaval in the Lake Chad Basin, which straddles Nigeria, Cameroon, Chad and Niger “one of the worst crises in today’s world” and said it must not become a “forgotten crisis.”

Over nine million people across the basin urgently need humanitarian aid, he said, and 6.3 million aren’t getting enough to eat.

At a high-level conference Friday on the sidelines of the General Assembly’s annual ministerial meeting, the U.N. humanitarian office said donors pledged $163 million of the $542 million needed this year. Major donors included Belgium, Italy, Britain and the United States.

Assistant Secretary-General Toby Lanzer, the humanitarian coordinator for the Sahel, said “the Lake Chad Basin crisis is one of the most acute emergencies in the world.”

“The situation of many affected communities has deteriorated beyond alarming levels,” he said. “If we do not act fast, and do more, especially in areas that were previously inaccessible, thousands of people will die.”

As a result of Boko Haram’s attacks, Eliasson said, civilians have been killed, homes torched, possessions looted and livelihoods destroyed.

“Tens of thousands of people in northeastern Nigeria are living in famine conditions,” he said.

Eliasson said the abduction of more than 200 schoolgirls from Chibok in Nigeria in April 2014 “is a horrific example of the use of sexual violence as a tactic of war and terrorism.”

He called for the immediate release of all those abducted and said the United Nations is “actively looking into” a request by Nigeria’s President Muhammadu Buhari for U.N. assistance in negotiating the release of the Chibok girls. He said the U.N. is in contact with Mohammed Ibn Chambas, who heads the U.N.’s West Africa office, “to advise on how we can be helpful.”

U.S. Ambassador Samantha Power told the meeting that the United States has provided more that $318 million in humanitarian aid to the region since 2015 and she announced an additional $41 million in assistance.

As an example of “the human stakes,” she cited U.N. estimates that an estimated 134 children will die every day of severe acute malnutrition in Nigeria’s Borno State unless they are treated. “And this is just a sliver of the consequences if we come up short,” Power said.

U.N. humanitarian chief Stephen O’Brien said he is “very encouraged” by Friday’s pledges, which will be used “to rapidly scale-up life-saving assistance to the millions of people that urgently need our help.” But the U.N. said $379 million is still needed this year.