RAMALLAH, July 5 (Xinhua) -- Palestine on Monday rejected the results of the ballistic investigation attended by U.S. experts into the gunshot that killed veteran Palestinian-American journalist in northern West Bank in May.

Earlier in the day, the Israeli army announced that the investigation could not determine the party responsible for the killing of Shireen Abu Akleh, the reporter of the Qatari Al-Jazeera news channel in the Palestinian territories.

Palestinian presidential spokesman Nabil Abu Rudeineh said in a statement that the Palestinian side "holds Israel fully responsible for the killing of Abu Akleh" and called on the United States "to maintain its credibility."

On Saturday, the bullet that killed Abu Akleh was received by Michael Wenzel, the U.S. security coordinator for Israel and the Palestinian Authority, for a professional and independent ballistic examination.

The ballistic test was conducted in an Israeli forensic laboratory with experienced representatives from the United States attending all the stages of the test to determine the weapon from which it was fired, the Israeli military said in a statement.

"Despite the efforts made, it has been found that in light of the condition of the bullet and the quality of the markings on it, it is not possible to determine whether the bullet was fired from the weapon tested or not," the statement added.

By summarizing both Israeli and Palestinian investigations, the U.S. security coordinator said in a statement that gunfire from Israeli positions was "likely responsible" for the death of Abu Akleh but no reason was found "to believe that this was intentional."

Abu Rudeineh said that the Palestinian side "won't accept, under any circumstances, the tampering with the outcome of the Palestinian investigation."

"We will pursue the case of her (Abu Akleh) assassination in international courts, especially before the Criminal Court," he added.

Abu Akleh, 51, a Palestinian Christian born in Jerusalem, was shot by a live bullet in the head on May 11 while covering an Israeli army incursion into the Jenin refugee camp in the northern West Bank.

The incident drew widespread Palestinian, Arab and international condemnation.