Israeli Prime Minister Benjamin Netanyahu is appearing before an internal commission investigating Israel's raid on a flotilla of ships taking aid to Gaza.
Mr Netanyahu says Israel acted according to international law during the incident on 31 May.
The deaths of nine Turkish activists when Israeli commandos stormed their ship in international waters caused a diplomatic crisis between Israel and Turkey, the BBC reports.
At the time Israel said the activists were determined to attack its soldiers, although Turkey described the killings as state sponsored terrorism.
In coming days Mr Netanyahu, the Defence Minister and the army's chief of staff will give evidence to the Commission of Inquiry, which was only set up after international pressure and which some observers say will not really get to the cause of why the operation went so badly wrong.
Sir Geoffrey Palmer, a former prime minister of New Zealand, will head a United Nations' inquiry into the attack.