Israel's bombing of Syrian military assets and its entry into the UN-patrolled buffer zone on the Golan Heights show it fears the worst from the end of the Assad clan's rule, analysts told AFP.
"The Israeli government... is operating on a worst-case scenario with little to no nuance," said Yossi Mekelberg, a Middle East specialist at Chatham House in London.
As soon as rebel forces seized Damascus, Syrians swarmed the notorious Saydnaya prison, desperate for news of loved ones who vanished under ousted president Bashar al-Assad's rule.
"I am waiting in the hope that one of my relatives will be found," said 25-year-old Youssef Matar, camped outside the feared Y-shaped prison since Sunday.
He said 10 of his family members were arrested "for no reason, just because we are from Daraya", a Damascus suburb pivotal in the 2011 uprising.
"I'm going to stay until I know if they're dead or alive."
Since the overthrow of Syrian president Bashar al-Assad, Iran has started to distance itself from their longtime alliance, instead stressing the history of friendship between the two countries.
Rebels advanced from their stronghold in the northwestern city of Idlib to the capital Damascus in less than two weeks, ousting Assad on Sunday and ending 50 years of rule by his clan.
Iranian officials and state media have since shifted their tone on the rebels, calling them "opposition groups" instead of "terrorists".
Syrians lived in terror for decades of what went on behind the concrete walls of Damascus's security compound. Now the Assad dynasty has been toppled, its dungeons and torture chambers are giving up their secrets.
Rebel fighters stand guard at the entrances to the forbidden city in the capital's Kafr Sousa district, where the feared security services had their headquarters alongside government offices.
Turkey has expanded its border crossing capacities to accommodate the surge in Syrian refugees seeking to return home following the fall of Bashar al-Assad, the interior minister has said.
Following Assad's ouster on Sunday, hundreds flocked to Turkey's southern border with Syria, with Ankara quickly moving to expand its crossing facilities, Interior Minister Ali Yerlikaya told reporters in remarks published on Tuesday.
"Although we had a daily capacity to accommodate 3,000 crossings, we have increased that to between 15,000 and 20,000," Yerlikaya said.
Once celebrated as an advocate of women's rights in the Middle East, Syria's British-born former first lady Asma al-Assad has fled into exile with her husband, with UK officials saying she is not welcome to return to London.
Asma al-Assad, 49, her husband and three children have sought refuge in Moscow after rebels ousted Bashar al-Assad from power, according to Russian state news agencies, although the Kremlin has not confirmed the reports.
Syria's new transitional prime minister on Tuesday said it was time for "stability and calm" in the country, two days after longtime president Bashar al-Assad was toppled by rebels in a lightning offensive.
The rebels appointed Mohammad al-Bashir as the transitional head of government to run the country until March 1, a statement said.
"Now it is time for this people to enjoy stability and calm," Bashir told Qatar's Al Jazeera television in his first interview since being appointed.
Australia's prime minister toured the charred wreckage of a synagogue on Tuesday, urging the nation to unite in the face of an "evil" arson attack.
Counter-terror police are hunting for three suspects believed responsible for torching the Adass Israel Synagogue in the early hours of Friday.
The blaze was met with international condemnation, while a leading Jewish human rights group has warned Australia may no longer be safe for Jewish visitors.
Israel's Prime Minister Benjamin Netanyahu dismissed corruption charges against him as 'ridiculous' in court on Tuesday, becoming the country's first sitting premier to face criminal trial.
Israeli media called it a "historic day" as Netanyahu faced charges of bribery, fraud and breach of public trust in three separate cases while running a country at war.
But Netanyahu rejected the charges, saying: "There's no corruption, no fraud. It is just ridiculous."
Donald Trump does not take office until January 20, but on the world stage he is already acting as if he is US president.
President-elect Trump has stamped his seal on US diplomacy on crises in Syria and Ukraine as his second spell in the White House approaches.
World leaders have jostled to talk to Trump and he was treated as the guest of honor at the grand reopening of the Notre Dame cathedral in Paris on the weekend.
Lame-duck, single-term President Joe Biden, 82, was conspicuous by his absence at the ceremony, as he increasingly fades into the background.
