A board of inquiry into an Israeli attack in Lebanon that killed four UN military observers in July was unable to determine why the attacks were not halted despite repeated appeals from UN personnel, UN spokesman Stephane Dujarric said Friday.

In a statement issued for UN Secretary-General Kofi Annan, Dujarric said the Board noted that the Israeli authorities accepted full responsibility for the attack on the UN post at Khiyam and apologized for what they say was an "operational level" mistake.

The Board was appointed by the UN Department of Peacekeeping Operations (DPKO) as standard procedure in such circumstances.

Dujarric pointed out that the Board did not have access to operational or tactical level IDF commanders involved in the incident.

Therefore, it was unable to determine why the attacks on the UN position were not halted, despite repeated demarches to the Israeli authorities from UN personnel, both in the field and at Headquarters, he said.

The report concludes that all standard operating procedures were followed and no additional actions could have been taken by UN personnel that would have changed the outcome, Dujarric added.

"The secretary-general once again pays tribute to the four who gave their lives in the cause of peace, and reiterates his heartfelt condolences to their families," he said.

Source: Xinhua