Since President Bashar al-Assad fled Syria, Israel has mounted a military offensive in the country unlike anything it has conducted there in decades, fearing chaos that could spill across the border.
The Israeli military has said that its fighter jets have launched hundreds of airstrikes to prevent “terrorist elements” from obtaining the Syrian military’s sophisticated arms.
Israeli soldiers have also seized a demilitarized buffer zone that served as the de facto border between the two countries. They have also captured Syrian military posts inside territory formerly under full Syrian control.
Israel and Syria last fought a major war in 1973. Since then, the border mostly stayed quiet. Over the past few years, Israel has targeted Iranian officials and militias in Syria as part of the country’s shadow war with Iran. Mr. al-Assad’s regime was closely aligned with Tehran, Israel’s regional foe.
But after Mr. al-Assad was deposed on Dec. 8, Israel unleashed a far more public and extensive offensive. Israeli warplanes and battleships bombarded more than 350 targets, including Syrian military bases, chemical weapons caches, antiaircraft batteries and long-range missiles, according to the Israeli government in a statement on Dec. 10. Since then, the Syrian Observatory for Human Rights, a monitoring group, has reported further strikes.
Israeli troops have also marched into Syrian territory in the largest overt operation there since the 1973 war. After that conflict, both sides had agreed that United Nations peacekeepers would monitor a 155-square-mile demilitarized zone between their forces.
Israeli forces now hold the peak of Mount Hermon, the highest point in Syrian territory, as well as other positions deeper inside Syria.
It is unclear how long they will stay.
Ahmad al-Shara, whose Hayat Tahrir al-Sham rebel faction led the campaign that toppled Mr. al-Assad, criticized the Israeli operation.
Mr. al-Shara pledged that Syria would abide by a 1974 cease-fire agreement with Israel, and argued that the downfall of Mr. al-Assad had ended the threat of Iranian militias menacing Israel from Syrian territory.
Israeli leaders have suggested that Israeli troops will stay in newly captured Syrian territory until “another arrangement is found.” They have referred to Hayat Tahrir al-Sham as a terrorist group, appearing to reject Mr. al-Shara’s assurances for the time being.
“The collapse of the Syrian regime created a vacuum on Israel’s border and in the buffer zone,” said Benjamin Netanyahu the Israeli prime minister. “Israel will not permit jihadi groups to fill that vacuum and threaten Israeli communities.”