The families of senior figures in the Assad regime were fleeing Syria on Monday night, ahead of an anticipated US-led strike against regime targets, Israeli television reported.

“The families of some of the heads of the regime” were flying out of Latakia Airport in the west of the country, Channel 2 News said. The airport happens to be named after President Bashar Assad’s late older brother, Bassel, who had been slated to take over as president from their father, Hafez Assad, but was killed in a car accident in 1994.

Israeli media Monday night assessed that the likelihood of a US-led strike on Assad regime targets was all but certain in the wake of an alleged chemical weapons attack last Wednesday in which the regime killed hundreds of civilians outside Damascus. The Channel 2 report said that the US was believed likely to give Israel advance warning of any such strike, to enable Jerusalem to prepare for any repercussions.

The same TV station had reported on Saturday that the chemical shells last Wednesday were fired by the 155th Brigade of the 4th Armored Division of the Syrian Army, a division under the command of another of the Syrian president’s brothers, Maher Assad.

A senior Syrian official on Monday issued a first direct warning that if attacked, his country would retaliate against Israel. Khalaf Muftah, a senior Baath Party official, said in a radio interview that Damascus would consider Israel “behind the [Western] aggression and [it] will therefore come under fire.

“We have strategic weapons and we’re capable of responding,” he said. “Normally the strategic weapons are aimed at Israel.”

His words were echoed by Iranian officials. ”No military attack will be waged against Syria,” said Hossein Sheikholeslam, a member of Iran’s Islamic Consultative Assembly. “Yet, if such an incident takes place, which is impossible, the Zionist regime will be the first victim of a military attack on Syria.”

Nonetheless, Israeli military sources reiterated on Monday night their estimation that it was “highly unlikely” that Syria would directly strike at Israel in response to outside military intervention, since this would prompt an Israeli response that would “break the tie” between Assad and the rebel forces seeking to oust him.

Israel is concerned, however, that Syria might try to retaliate for a US-led attack via terror groups in south Lebanon or internationally, the sources said.

“Our hand is always on the pulse,” Prime Minister Benjamin Netanyahu said Sunday, condemning the alleged Assad regime use of chemical weapons, and threats from Syria to attack Israel. “Our finger is a responsible one and if needed, is on the trigger. We will always know how to protect our citizens and our country against those who come to injure us or try to attack us.”