An independent panel of U.N. investigators says the human rights situation in Syria has sharply deteriorated, with “gross violations” growing in number, pace and scale.

The panel's Brazilian chairman, Paulo Pinheiro, told the U.N. Human Rights Council in Geneva Monday that “egregious violations” happen so often that his team has not been able to investigate them all.

He also said there is an increasing number of Islamist militants in Syria, and that their presence tends to push rebels opposed to Syrian President Bashar al-Assad toward more radical positions.

Syria's ambassador to the United Nations in Geneva, Faysal Khabbaz Hamoui, criticized the report. He said members of the international community are working to make the crisis in Syria worse.

What began as protests against Mr. Assad's rule in March, 2011, and a subsequent government crackdown has progressed to daily clashes between Syrian forces and rebels.

The U.N. panel says the fighting amounts to a non-international armed conflict, and that there are “reasonable grounds” to believe government forces, pro-Assad militia groups and anti-government fighters have all committed war crimes and human rights violations.