The UN Human Rights Council has passed a resolution demanding a halt to Israel's offensive in the Gaza Strip.
UN special rapporteur John Dugard is to lead a fact finding mission
Twenty-nine of the council's 47 member states backed the resolution, 11 voted against, five abstained and two members were absent.
The recently-formed council also said it would send a fact-finding mission to investigate the human rights situation in the Palestinian territories.
It will be led by John Dugard, a UN special rapporteur on human rights.
Israel, backed by the US and European countries, has accused the UN council of bias, because it did not also criticise violence perpetrated on the Palestinian side.
On Wednesday, Mr Dugard said Israel was violating the most fundamental norms of humanitarian and human rights law in its actions in Gaza.
Its military operation violated prohibitions on collective punishment, intimidation, while last week's arrest of officials from the governing Hamas movement appeared to constitute hostage-taking that was prohibited by the Geneva Conventions, Mr Dugard said.
"I am concerned with the law. And here it is clear that Israel is in violation of the most fundamental norms of humanitarian law and human rights law," he Mr Dugard said.
The resolution, which was brought by Islamic states, expressed "grave concern at the violations of the human rights of the Palestinian people caused by the Israeli occupation, including the current extensive Israeli military operations".
The Council urged "Israel, the occupying power, to immediately release the arrested Palestinian ministers... and all other arrested Palestinian civilians".
The text also called "for a negotiated solution to the current crisis".
European Union member states on the council, including Britain, France and Germany, voted against the resolution.
Finland, speaking on behalf of the EU, took the floor to say that the situation needed to be addressed in a "more balanced manner".
The resolution did urge "all concerned parties to respect the rules of international humanitarian law and to refrain from violence against civilians".
This text was added at the last moment in an unsuccessful bid to placate European concerns about what they saw as a one-sided resolution, correspondents said.
The resolution went on to call on both sides to "treat under all circumstances all detained combatants and civilians in accordance with the Geneva Conventions".
The United States, which is only an observer at the Council, called the resolution a wasted opportunity.
"A historic opportunity to address the human rights situation in a fair, equitable and balanced way has instead resulted in an unbalanced effort to single out and focus on Israel alone," US Ambassador to the UN in Geneva Warren Tichenor said.
Israel's ambassador, Itzhak Levenon said: "We find ourselves in an absurd situation in which the Human Right Council convened into urgent session ignores the rights of one side and holds a special meeting to defend the rights of the other side".
However, the Palestinian representative, Muhammad Abu Koash called it a "very mild and diluted resolution".
"While we gather here in this hall, Israeli tanks are moving and shelling Palestinians, the office of our parliament has been besieged by Israeli troops," he told the Council.