Syria’s new authorities launched an operation in a stronghold of ousted president Bashar al-Assad on Thursday, with a war monitor saying three gunmen affiliated with the former government were killed.

Assad fled Syria after an Islamist-led offensive wrested from his control city after city until Damascus fell on December 8, ending his clan’s five-decade rule.

After 13 years of civil war sparked by Assad’s crackdown on democracy protests, Syria’s new leaders from Islamist group Hayat Tahrir al-Sham (HTS) face the monumental task of safeguarding the multi-sectarian, multi-ethnic country from further collapse.

Rooted in Syria’s branch of Al-Qaeda, a Sunni Muslim jihadist group, HTS has moderated its rhetoric and vowed to ensure protection for minorities, including the Alawite community from which Assad hails.

With 500,000 dead in the war and more than 100,000 missing, the new authorities have also pledged justice for the victims of abuses under the deposed ruler.

On Thursday, state news agency SANA said security forces launched an operation against pro-Assad militias in the western province of Tartus, “neutralising a certain number” of armed men.

According to the Syrian Observatory for Human Rights monitor, three gunmen linked with Assad’s government were killed in the operation.

It comes a day after 14 security personnel of the new authorities and three gunmen were killed in clashes in the same province when forces tried to arrest an Assad-era officer, according to the Observatory.

The Britain-based monitor said the wanted man, Mohammed Kanjo Hassan, was a military justice official who had “issued death sentences and arbitrary judgements against thousands” of detainees at the notorious Saydnaya prison complex.

The Saydnaya complex, the site of extrajudicial executions, torture and forced disappearances, epitomised the atrocities committed against Assad’s opponents.

The fate of tens of thousands of prisoners and missing people remains one of the most harrowing legacies of his rule.

During the offensive that precipitated Assad’s ousting, rebels flung open the doors of prisons and detention centres around the country, letting out thousands of people.

In central Damascus, relatives of some of the missing have hung up posters of their loved ones, in the hope that with Assad’s ouster, they may one day learn what happened to them.

World powers and international organisations have called for the urgent establishment of mechanisms for accountability.

But some members of the Alawite community fear that with Assad gone, they may be at risk of attacks from groups hungry for revenge or driven by sectarian hate.

On Wednesday, angry protests erupted in several areas around Syria, including Assad’s hometown of Qardaha, over a video showing an attack on an Alawite shrine that circulated online.

The Observatory said that one demonstrator was killed and five others wounded “after security forces… opened fire to disperse” a crowd in the central city of Homs.

The transitional authorities appointed by HTS said in a statement that the shrine attack took place early this month, with the interior ministry saying it was carried out by “unknown groups” and that republishing the video served to “stir up strife”.

On Thursday, the information ministry introduced a ban on publishing or distributing “any content or information with a sectarian nature aimed at spreading division and discrimination”.

In one of Wednesday’s protests over the video, large crowds chanted slogans including “Alawite, Sunni, we want peace”.

Assad long presented himself as a protector of minority groups in Sunni-majority Syria, though critics said he played on sectarian divisions to stay in power.

In Homs, where the authorities imposed a nighttime curfew, 42-year-old resident Hadi reported “a vast deployment of HTS men in areas where there were protests”.

“There is a lot of fear,” he said.

In coastal Latakia, protester Ghidak Mayya, 30, said that for now, Alawites were “listening to calls for calm”, but putting too much pressure on the community “risks an explosion”.

Noting the anxieties, Sam Heller of the Century Foundation think tank told AFP Syria’s new rulers had to balance dealing with sectarian tensions while promising that those responsible for abuses under Assad would be held accountable.

“But they’re obviously also contending with what seems like a real desire on the part of some of their constituents for what they would say is accountability, maybe also revenge, it depends on how you want to characterise it,” he said.

Since HTS and its allies swept to power earlier this month, a bevy of delegations from the Middle East, Europe and the United States have visited Damascus seeking to establish ties with the country’s new rulers.

A delegation from Iraq met with the new authorities Thursday to discuss “security and stability needs on the two countries’ shared border”, Iraqi state media said, while Lebanon, which has a fraught history with Syria, said it hoped for better ties with its neighbour going forward.