Either Syrian rebels or the Damascus regime have used chemical weapons in the country's two-year civil war, Israel’s newly appointed Minister of Intelligence and Strategic Affairs, Yuval Steinitz, said on Wednesday.
"It's apparently clear that chemical weapons have been used against civilians by the rebels or by the government," Steinitz told Army Radio.
"This is very concerning for us and we must deal with it urgently," he said.
Syrian rebels and the regime exchanged accusations of chemical weapons use on Tuesday for the first time since the March 2011 uprising, which has already claimed the lives of over 70,000 people.
Russia and Iran, both allies of President Bashar al-Assad, said they had received information proving rebels had used chemical agents in an attack in the northern province of Aleppo, which an official toll said killed 31 people.
The United States, which is among a number of Western and Arab countries supporting the Syrian opposition leadership, said the accusations were baseless.
The Israeli army said in a statement that four injured Syrians were treated by IDF soldiers.
"Early this morning four wounded Syrians came to the Israel-Syria border and received medical treatment from soldiers. Two... were taken to Israeli hospitals," it said.
The reports of chemical weapons use triggered a growing number of U.S. lawmakers on Capitol Hill to renew calls for the Obama administration to arm Syrian rebels fighting the ruthless dictatorship.
Republican Senator Sen. Lindsey Graham said that refraining from taking decisive measures to secure chemical weapons sites would leave the United States looking like a “paper tiger.”
“I’ve never been more worried about weapons of mass destruction falling into terrorists’ hands than I am right now,” said the senator from South Carolina. “And I would urge the president and Republican leaders to openly embrace ending this conflict sooner rather than later with a post-Assad plan that focuses on securing these chemical weapons sites.”
Graham and Sen. John McCain (R-Ariz.) said in a later statement if the use of chemical weapons was substantiated, the administration should arm vetted rebel groups, launch targeted strikes against Assad’s missile batteries and establish safe zones in Syria, The Hill reported.
Rep. Eliot Engel (D-N.Y.) also introduced legislation earlier this week to arm vetted rebel groups.
White House press secretary Jay Carney declined to confirm reports that chemical weapons had been used, saying only that the White House is “looking carefully at the information as it comes in.”
Israel has repeatedly expressed concern that Syria's chemical arsenal could fall into the hands of anti-Israel terrorists such as Hizbullah, or an Al Qaeda-linked group fighting with the rebels.