A record number of humanitarian workers were attacked last year, driven partly by increased use of armed drones, the United Nations said on Wednesday, calling the trend "appalling".

Some 907 aid workers were killed, injured or kidnapped in 2025 versus 833 the year before, according to the Aid Worker Security Database, a platform funded by Canada and Australia that compiles major security incidents affecting aid workers.

Of those, 350 were killed, down slightly from a record 387 in 2024.

United Nations Secretary-General Antonio Guterres said the level of violence was appalling and urged states to respect the rules of war and hold perpetrators accountable.

"Serving others has become more dangerous than ever," he said, ahead of UN ceremonies planned for World Humanitarian Day with flags at half-staff in New York and Geneva in honour of those killed.

UN aid chief Tom Fletcher said the proliferation of cheap and adaptable armed drones in conflicts has increased the risks. In March, drone strikes hit Goma in the eastern Democratic Republic of Congo, killing at least three people including a French aid worker, while aid convoys in Sudan and Ukraine have been repeatedly hit.

Gaza was by far the most deadly place for aid workers in 2025 with 186 humanitarians killed there last year, the database showed, followed by Sudan. The UN Palestinian refugee agency has reported at least 393 staff killed there since the Israel-Gaza war began on October 7, 2023.

Israel, which is fighting Hamas militants in Gaza, has said it goes to great lengths to avoid all civilian casualties.

UNRWA's former chief Philippe Lazzarini said earlier this year he was seeking a high-level panel to investigate staff deaths.

Bushra Khalidi, global humanitarian policy lead at Oxfam, called for greater protections for aid workers, saying: "We're witnessing an assault on humanitarian action itself."