UNITED NATIONS (AP) – A record number of aid workers were killed in conflicts around the world last year—more than half after the Israel-Hamas war started on October 7—and this year may become even deadlier, the United Nations said Monday.

The 280 aid workers from 33 countries killed in 2023 was more than double the previous year’s figure of 118, the UN Office for the Coordination of Humanitarian Affairs known as OCHA said in a report on World Humanitarian Day.

UN Secretary-General Antonio Guterres tweeted that honoring the humanitarians killed in the deadliest year on record is not enough.

“In Sudan & many other places, aid workers are attacked, killed, injured & abducted. We demand an end to impunity so that perpetrators face justice,” the UN chief said.

OCHA said this year “may be on track for an even deadlier outcome,” with 172 aid workers killed as of August 7, according to a provisional account from the Aid Worker Security Database.

More than 280 aid workers have been killed in the war in Gaza, now in its 11th month, mainly in airstrikes. The majority of them are Palestinians who worked for the UN agency helping Palestinian refugees known as UNRWA, according to OCHA. It said that “extreme levels of violence in Sudan and South Sudan “also have contributed to the death toll both this year and last.

The UN’s acting humanitarian chief, Joyce Msuya, said in a statement that “the normalization of violence against aid workers and the lack of accountability are unacceptable, unconscionable and enormously harmful for aid operations everywhere.”

In a letter to the 193 UN member nations, 413 humanitarian organizations around the world said: “The brutal hostilities we are seeing in multiple conflicts around the world have exposed a terrible truth: We are living in an era of impunity.”

The aid organizations appealed to all countries, the wider international community and all parties to conflicts to protect civilians and aid workers and hold perpetrators to account.

World Humanitarian Day commemorates the August 19, 2003, terrorist bombing of the UN offices at the Canal Hotel in Baghdad which killed 22 UN staff members including the top UN envoy to Iraq, Sergio Viera de Mello, a Brazilian diplomat.

At a ceremony at UN headquarters Monday before the tattered UN flag retrieved from the hotel that day, dozens of current UN staff members and relatives of some of the victims stood in silent tribute to their memory—as did many watching around the world.