The blue helmet from Indonesia was deployed with the UN Interim Force in Lebanon (UNIFIL), which reported that a projectile exploded at its position near Adchit Al Qusayr, located in the south of the country.

Another peacekeeper was seriously injured in the blast and remains in hospital.

UNIFIL did not know the origin of the projectile and has launched an investigation to determine the circumstances.

“No one should ever lose their life serving the cause of peace,” the mission said.

Ensure safety of UN personnel

The Secretary-General strongly condemned the incident, which occurred within the context of the escalating conflict in the Middle East.

“This is one of a number of incidents that have jeopardized the safety and security of peacekeepers, including over the past 48 hours,” UN Spokesperson Stéphane Dujarric said in a statement.

“Once again, the Secretary-General calls on all actors to uphold their obligations under international law and to ensure the safety and security of UN personnel and property at all times.”

Possible war crimes

The UN chief recalled that attacks on peacekeepers are grave violations of international humanitarian law and of UN Security Council Resolution 1701 (2006) and may amount to war crimes.

UNIFIL supports implementation of the resolution, which brought an end to hostilities between Israeli forces and Hezbollah that erupted nearly two decades ago. Read more in our explainer.

“There will need to be accountability,” the statement said.

Appeal for de-escalation

The Secretary-General expressed his deepest condolences to the family, friends, and colleagues of the deceased peacekeeper, and to the country of Indonesia. He wished a full and fast recovery to the injured officer.

Mr. Guterres also extended his deepest appreciation to the men and women serving with UNIFIL, underscoring the importance of their safety, security and freedom of movement.

The UN urged the parties to de-escalate immediately and fully adhere to their obligations under the Security Council resolution.

More than 50 health workers killed this month

Meanwhile, the World Health Organization (WHO) reported the loss of another medical professional amid the escalation.

“Israel's expanding military operations in southern Lebanon have resulted in the death of yet another health worker today,” WHO chief Tedros Adhanom Ghebreyesus said on Sunday in a statement posted on X.

The paramedic was killed in a strike on an ambulance in the town of Bint Jbeil, while a medical warehouse there was destroyed in an attack.

“Prior to today's strikes, WHO has verified that 51 Lebanese health workers have been killed since 2 March, including nine paramedics just yesterday,” Tedros said.

“Attacks on health facilities must cease immediately. This cannot become the norm.”