By Stephanie Nebehay
GENEVA (Reuters) - The United Nations gave its investigators another year to gather evidence of war crimes in Syria on Friday, saying they had already found horrifying first-hand accounts of murder, torture and rape.
The U.N. Human Rights Council condemned "gross violations" by Syrian government forces and allied militia, including shelling of populated areas and massacres during the two-year-old conflict.
Rebels were also carrying out atrocities, but not on the same scale, the 47-member Geneva forum added in a resolution brought by Arab and Western states.
"While the Syrian authorities have failed to prosecute alleged perpetrators, the international community must ensure that impunity will not prevail," said Ireland's ambassador Gerard Corr, speaking on behalf of the European Union (EU).
Only Venezuela voted against the resolution and five other countries abstained. Neither China nor Syria's ally Russia are members this year, so cannot vote.
Syria's ambassador Faysal Khabbaz Hamoui angrily rejected the text as "an aberration".
"There were no condemnations of the dangerous role of Turkey and Qatar to fuel this crisis through arming, financing and sending combatants of al Qaeda and terrorists," he said.
CITIES BOMBED, CAPTIVES KILLED
The Council renewed the mandate of its commission of inquiry, led by Brazilian expert Paulo Pinheiro, that has been documenting crimes committed during the conflict in which at least 70,000 people have been killed.
Pinheiro told the Council this month the Syrian government has stepped up indiscriminate heavy bombardments of cities while rebels were executing prisoners condemned in their own makeshift courts without due process.
"The commission of inquiry's latest report details horrifying first-hand accounts of murders, deliberate and systematic torture, rape and other forms of sexual and gender-based violence, targeted destruction of protected civilian property, including schools and mosques, and the use of children in fighting forces," U.S. ambassador Eileen Chamberlain Donahoe said on Friday.
"Those responsible for crimes against the Syrian people must be held accountable," she said, adding that President Bashar al-Assad had "lost all legitimacy and must step aside".
The resolution was the subject of heavy negotiations during much of the four-week annual session that ends later on Friday.
Switzerland and some EU states wanted the Council to make an explicit mention of the International Criminal Court (ICC) as the way to pursue criminal investigations, diplomats said.
But Arab states opposed the move and the final text noted "the relevance of referrals to the appropriate international criminal justice mechanism under appropriate circumstances".
"We said it was not the job of the Human Rights Council to look to the ICC," an Arab diplomat told Reuters.
Syria is not a party to the Rome Statute which set up the ICC, so the only way the Hague-based court can investigate the conflict is if it receives a referral from the U.N. Security Council, where major powers remain divided on the issue.
(Reporting by Stephanie Nebehay; Editing by Andrew Heavens)