At a news conference, Tutu said Israel's contention that a technical fault caused the shells to hit two homes in the Gaza town of Beit Hanoun, a border area where fighters fire rockets at southern Israel, "fell short of accountability".
The Nobel Peace Prize laureate planned to present a report about the incident to the UN Human Rights Council in Geneva at a session in September. Israel has not cooperated with the mission, accusing the council of being biased against it.
"We are at the stage of shock ... by what we subsequently heard from the survivors of the
He also urged fighters to stop launching rockets at Israel.