Syria possesses the largest chemical weapons stocks in the world, including missiles and rockets that can reach any point in Israel, Israel Defense Forces Deputy Chief of General Staff Maj. Gen. Yair Naveh said on Sunday.

Speaking at a ceremony to commemorate fallen soldiers and mark 30 years since the Battle of Sultan Yacoub between Syria and Israel during the 1982 Lebanon War, Naveh said, "Syria today has the largest chemical weapons stockpile in our neighborhood. These missiles can reach any point in Israel and therefore we must remain vigilant."

The deputy chief of staff's comments reflect a growing concern within the Israeli military in recent months that weapons of mass destruction, particularly chemical weapons stashed in large quantities in Syria, will fall into the hands of rebels and then terrorist groups.

Commenting on crimes perpetrated by Syrian President Bashar al-Assad's army to crush the uprising against his rule, Naveh warned, "What the Syrians are doing to their own people they would do to us if they got the chance."

In March, the IDF said that if Hezbollah acquires chemical weapons and advanced anti-aircraft systems, Israel will have to recalibrate its planned defenses to Hezbollah attacks. The IDF is concerned that more lethal and advanced weapons could be transferred from Syria to Hezbollah if the Syrian leadership finds itself in a desperate situation. A senior defense official told Israel Hayom in March that the transfer of chemical weapons from Syria to Hezbollah would be tantamount to a declaration of war, and added that Israel would not accept such a move and would take action to prevent it.

Syria has transferred advanced weapons to Hezbollah control in recent years, but the weapons have remained on Syrian soil in accordance with Assad's instructions, to avoid their possible destruction by Israel. With the increasing belief that Assad's rule is expected to end in the near future, some analysts have warned he may decide to transfer arms to Hezbollah in Lebanon. The delivery could include a large number of long-range missiles, advanced anti-aircraft systems that could threaten Israel Air Force flights in the north, and chemical weapons.

Syria is believed to possess the world's largest stockpile of chemical weapons, including some of the deadliest chemical agents known, such as sarin and the nerve agent VX. Their chemical agents have already been integrated in warheads mounted on advanced Scud missiles.

The weapons are currently under the tight supervision of military forces loyal to Assad, but may be transferred to Hezbollah — possibly even at Iran's behest — because Lebanon is currently perceived as more stable than Syria. "We are seeing a paradoxical process unfold, in which Syria is undergoing a process of 'Lebanonization' and vice versa," a senior Israeli defense official told Israel Hayom. "Syria, which was an island of stability in the past is now being torn apart by military clashes. Lebanon is now perceived as being the more stable of the two," the official added.

Syrian activists estimate more than 13,000 people have died since the uprising in Syria erupted 15 months ago.

Meanwhile, reports emerging from Syria on Sunday said rebels took over a Syrian Air Force base in Homs which stocked air defense weapons systems, including surface-to-air missiles.

According to an Al-Arabiya report, the rebels managed to seize surface-to-air missile batteries that may give them an advantage in the struggle against the Syrian Air Force. Officers and soldiers at the base reportedly defected from Assad's troops and joined the rebel forces after the commander of the battalion there called on them to choose between going home or joining the uprising. A spokesman for the rebels claimed that they all chose to defect.

The Syrian army was left with no choice but to bomb the base. The attack by the Syrian army also included the firing of shells, mortars and rockets at the central district of Homs, as part of a renewed effort to take over areas captured by the rebels.

Government forces shelled rebel-held cities and villages, killing at least 38 people in Homs, activists said. It was impossible to independently confirm the death toll.

The highest was in the central city of Homs and surrounding towns, where 17 people were killed, said Rami Abdul-Rahman of the Syrian Observatory for Human Rights. He said at least 16 Syrian forces were also killed in clashes throughout the country.

In the aftermath of clash in Homs, amateur video showed chaos in an underground medical treatment site where wounded and men lay strewn. Activists lifted one man to show the flesh ripped apart from the back of his leg, a dead boy and another man close to death.

Regime forces also shelled the southern city of Daraa and nearby villages, said Abdul-Rahman.

The military unleashed a new round of heavy shelling and sent reinforcements to a mountainous area near the coastal city of Latakia, where hundreds of rebels have set up a base and fierce fighting has raged in recent days.

The capture of the air force base on Sunday was the second significant advance by the rebels in a week, after they attacked a government target in Damascus last week. According to the British Sky News, some 600 rebel fighters were involved in an attack on a bus carrying Russian oil workers, and several of the workers were killed. Additionally, a residential building housing some oil workers was attacked by grenade launchers.

Meanwhile, Syria's main opposition group on Sunday picked a secular Kurd as its new leader after criticism that the former head was too autocratic and the group was becoming dominated by Islamists.

The opposition, hobbled by disorganization and infighting, is trying to pull together and appear more inclusive by choosing a member of an ethnic minority.

The opposition's disarray has frustrated Western powers eager to dislodge Assad but unwilling or unable to send in their own forces to do it. There has been some willingness to support the rebels with funds and arms, but the lack of a cohesive front or a single address has hampered the efforts as the bloodshed intensifies.

The choice of Abdulbaset Sieda as head of the Syrian National Council is aimed at achieving several goals for the main opposition group:

— Under outgoing leader Burhan Ghalioun, criticism mounted that the group was dominated by Islamists, especially the Muslim Brotherhood. Sieda is a secular.

— Sieda is also a Kurd, and his selection could be an incentive for Syria's minority Kurds to take a more active role in the uprising. Up to now they have stayed mostly on the sidelines.

— Selection of a member of a minority group could counter criticism that under Ghalioun, the umbrella organization was too autocratic. Sieda is seen as a neutral consensus figure.

"This is clearly an opportunity and there is clearly a need for a change," said Peter Harling of the Brussels-based International Crisis Group think tank.

However, key problems remain.

The SNC has only tenuous ties to the Free Syrian Army, which is doing most of the actual fighting against Assad's forces, and is itself little more than a disorganized collection of local militias.

Sieda, 56, an expert on ancient civilizations, is a longtime exile who lives in Sweden, like his predecessor, who is based in Paris. Activists actually doing the fighting in Syria worry that if they succeed in deposing Assad, the exiles will swoop in and take over.

The SNC must also gain the confidence of the international community, which is searching for effective ways to hasten the departure of Assad.

British Foreign Secretary William Hague said Sunday that he could not rule out military intervention in Syria, saying the situation there is beginning to resemble the violence that gripped Bosnia in the 1990s.

Hague told Sky News television that time was "clearly running short" to implement international envoy Kofi Annan's cease-fire plan. It was supposed to take effect on April 12 but never took hold.

Hague said Syria was "on the edge of collapse or of a sectarian civil war so I don't think we can rule anything out."

Many of Syria's estimated 2.5 million Kurds — more than 10 percent of the population — join Christians, Alawites and other key minorities whose fear for the future if Assad's secular regime collapses has deterred them from joining the uprising.

Sieda said he is in touch with the main Kurdish umbrella group, the Kurdish National Council. Its delegates walked out of an SNC gathering in March after the SNC failed to back its demands for Kurdish rights in a post-Assad state.

Mohieddine Sheik Ali, the Aleppo-based head of the Syrian Kurdish Democratic Unity Party, indicated Sieda has a tough task winning over minds. "We want real partnership as Kurdish parties. We do not want to be an appendix in any opposition group," he said.