Inside the abandoned homes of Assad's ruthless enforcers

Many, though, do want justice.

The leader of HTS has vowed to pursue the senior regime figures in Syria and asked other countries to hand over those who fled. Those wanted elsewhere have limited places to run.

Finding the men will be a challenge.

"While there is no confirmed information on the current whereabouts of senior regime figures like Jamil Hassan, Ali Mamlouk, and others, there are concerns that such individuals could benefit from political deals that enable them to evade justice," the Syrian Center for Media and Freedom of Expression (SCM) tells the BBC.

"Some are likely to have sought refuge in allied countries, complicating future extradition efforts, while others may still be in Syria, living discreetly."

On Hassan's street, neighbours speculate about where the vanished war criminal has gone.

His family left few clues in the apartment. But in the office is a certificate for Hassan's daughter signed by Hassan Nasrallah, the late leader of Lebanon-based Shia militant group Hezbollah, thanking her for her "help and support for this honourable resistance".

Several neighbours suggest he may be hiding in Lebanon or has transited through there, while the local shopkeeper says he thinks Hassan headed for the coast, perhaps to Latakia in the north - the heartland of the minority Alawite sect to which Assad and many of his closest allies belong.

Meanwhile, Lebanese newspaper Nida al-Watan reports that Mamlouk was smuggled across the border and into the Lebanese capital Beirut by Hezbollah, external - a long-time ally of Syria's Ba'ath government.

Hezbollah has not confirmed offering assistance to any regime figures, and the Lebanese government has said no Syrian officials targeted by international warrants were authorised to enter through legal crossings. Lebanese security services say Mamlouk is not in the country.

Syrian-British barrister Ibrahim Olabi says regime officials may have acquired new identities and passports, as they were powerful people backed by state institutions.

When it comes to getting justice, he adds, a lack of evidence is not the problem. It is more about finding them and getting them to a place where they can be held accountable.

The SCM says doing this will "require considerable resources, sustained political will, and international collaboration".

Failing to do so will send a "dangerous message that crimes, including war crimes and crimes against humanity, can go unpunished", it adds.

Ibrahim Olabi says he is hopeful that justice will be served.

"It will absolutely be a hunt," he says, but "the world now is a small place through social media, private investigators, political leverages".

Hassan's neighbours who were willing to talk say they hope he will one day be returned to Syria, far away from their street, to be punished.