WAR DRAGS ON: Government soldiers sit on a tractor holding their weapons on June 5 in Qusayr, central Syria's Homs Province (XINHUA/AFP)

The escalating civil war in Syria reached a new level of tension after revelations of chemical weapons use in the conflict that has been raging since March 2011. On April 25, U.S. intelligence agencies disclosed that they believed government forces may have used small-scale chemical weapons including Sarin agents in battles against anti-government forces. Since then, Britain, Israel, Turkey and others have voiced opposition to the Syrian Government's purported use of chemical weapons.

The Independent International Commission of Inquiry on Syria submitted a report to the UN Human Rights Council on June 4, claiming it had "reasonable grounds" to believe chemical weapons have been used by both sides in Syria. The sensitive topic of chemical weapons threatens to further intensify the conflict in the country, as it could become an excuse of foreign military intervention.

Conflicting accusations

The Syrian Government has denounced U.S. accusations, insisting that there is no evidence supporting claims of chemical weapons use. Rather, it claimed that the opposition used chemical weapons in Aleppo in March. On March 19, Syrian authorities declared that anti-government forces used rocket shells containing chemical materials in Aleppo, which caused at least 25 deaths and 130 injuries, and requested that the UN conduct an investigation. Syrian Information Minister Omran Zoabi condemned U.S. and British governments for what he called "shameless and ridiculous lies," noting that the missiles were launched in the opposition-controlled area near the Syria-Turkey border.

Despite endless mutual accusations between the government and the opposition, the truth remains unclear.

The chemical weapon crisis brought on by the U.S. intelligence network has spurred an international effort to discover the truth. On April 23, the Israeli military said the Syrian Government indeed used chemical weapons against opposition forces.

British Prime Minister David Cameron made a cautious statement on the issue. He said that Britain had obtained only limited evidence suggesting the Syrian Government used chemical weapons, and that more solid proof was needed before making a conclusion. The evidence Cameron referred to was from two autopsies that were carried out respectively by Britain and the United States. The investigation failed to conclude that poison gas was used, so it is too early to judge whether the Syrian Government used chemical weapons.

There is a major controversy over Washington's assessment of the issue. On April 24, White House spokesman Jay Carney said the evidence for Syrian chemical weapons use was inconclusive. With no firm evidence to accuse the Syrian Government, U.S. President Barack Obama has approached the matter cautiously. Obama said on April 26 that the intelligence assessment was still at the primary phase, and that more evidence was needed before making a final conclusion. However, U.S. Secretary of State John Kerry said on May 10 that the United States had obtained sufficient evidence proving the Syrian Government is using poison gas. But he also noted that further investigation was required to confirm the intelligence reports.