In an interview published in Al-Hayat, United Nations Secretary General Kofi Annan regarded the army’s version of the events as "strange."
The army’s investigation team examining the incident concluded Tuesday "beyond all doubt" that the casualties were not hurt as a result of Israeli shelling.
But the British newspaper The Independent on Wednesday quoted a former Pentagon battle damage expert, now with Human Rights Watch, who visited the site of the incident, as saying that "all the evidence points" to a "155mm Israeli land-based artillery shell" as the cause of the blast. He also called for an independent inquiry.
Annan also expressed sorrow and shock over the Israel Air Force strike in the Gaza Strip on Tuesday, in which seven Palestinian civilians were killed. He did not raise the possibility of a UN investigation of the incidents.
The UN chief called on Israel to abide by international law, saying that restraint should be practiced to prevent targeting civilians.