The experts, led by University of Sydney law professor Ben Saul, the UN’s special rapporteur on human rights and counter-terrorism, labelled the exploding pagers “a terrifying violation of international law”.

“These attacks violate the human right to life, absent any indication that the victims posed an imminent lethal threat to anyone else at the time,” the experts said in a joint statement issued from Geneva late on Thursday night.

“Such attacks require prompt, independent investigation to establish the truth and enable accountability for the crime of murder.”