Syria’s defence ministry says it has completed a military operation in the country’s western coastal region, after days of violence in which hundreds of people have been killed.

Security forces had “neutralized” loyalists of former president Bashar al-Assad in several towns in Latakia and Tartous provinces and were “paving the way for life to return to normal”, a ministry spokesman said.

A monitoring group says more than 1,500 people have been killed since Thursday, including 1,068 civilians.

Gunmen loyal to the Sunni Islamist-led government have been accused of carrying out revenge killings against members of Assad’s minority Alawite sect following a deadly ambush on a security patrol.

The interim President, Ahmed al-Sharaa, has said he will set up an independent committee to investigate the killings and insisted the perpetrators would be held accountable.

The violence is the worst in Syria since Sharaa led the lightning rebel offensive that overthrew Assad in December, ending 13 years of devastating civil war in which more than 600,000 people were killed and 12 million others were forced to flee their homes.

Defence ministry spokesman Hassan Abdul Ghani announced on X that the security operation in Latakia and Tartous had ended after “achieving all the specified objectives”.

“Our forces have neutralised the security cells and remnants of the former regime from the town of al-Mukhtareyah, the town of al-Mazairaa, the area of al-Zobar, and other locations in Latakia province, as well as Dalia town, Tanita town, and Qadmous in Tartous province, resulting in the thwarting of threats and securing the area,” he said.

He also said that public institutions in the region were now able to resume their work, adding: “We are preparing for the return of normal life and working to reinforce security and stability.”

Abdul Ghani promised that security forces would also “give the investigating committee the full opportunity to uncover the circumstances of these incidents, verify the facts and deliver justice to the oppressed”.

In an interview on Monday, Sharaa acknowledged that there were “many violations” following the outbreak of violence and promised to punish everyone responsible, including his own allies if necessary.

“Syria is a state of law. The law will take its course on all,” he told Reuters news agency.

“We fought to defend the oppressed, and we won’t accept that any blood be shed unjustly, or goes without punishment or accountability, even among those closest to us,” he said.

The government launched the operation in Latakia province in response to a growing insurgency by Assad loyalists in recent weeks. The region is the heartland of the Alawite sect, to which many of the former regime’s political and military elite belonged.

On Thursday, security personnel were ambushed by gunmen in the town of Jableh as they tried to arrest a wanted Assad regime official. At least 13 officers were reportedly killed.

Security forces responded by sending reinforcements to the region, who were joined by armed supporters of the government. Over the next four days, they stormed many Alawite towns and villages, where residents said they carried out revenge killings and lootings.

A widely shared video showed the bodies of at least two dozen men in civilian clothing, piled in the yard of a house, in al-Mukhtareyah. Elsewhere, accounts emerged of fighters searching for Alawite members and killing entire families on the spot.

Hiba, an Alawite woman in Baniyas, told the BBC that Chechen fighters loyal to the government had attacked her neighbourhood.

“Our neighbours were killed including children. They came and took everything, gold, everything… They stole all of the cars in the neighbourhood. They even went to the supermarket and they took everything from the shelves.”

“We were waiting for our turn. We didn’t know when it would come. We saw death, we saw people dying in front of us and now all of our friends, our neighbours, are gone,” she added. “They killed innocent people in cold blood who had nothing to do with any of this.”

An Alawite man whose family lives in Baniyas said in a voice message that a relative was kidnapped from his home by gunmen from Sharaa’s Islamist group, Hayat Tahrir al-Sham (HTS), who went door to door searching for Alawites.

“His mother made a mistake opening the door when she did. An HTS member fired between her legs… so she screamed,” he said. “Her son… ran to see what happened with her. When they [saw] him, they took him with them and disappeared. And they didn’t return.”

He also said residents of Alawite neighbourhoods of Baniyas were still hiding in their houses on Monday morning because they were too afraid to venture outside to see if it was safe.

The bodies of those killed had been buried in a mass grave near a shrine on the outskirts of the town, while those who were kidnapped had not yet returned, he added.

The Syrian Observatory for Human Rights, a UK-based monitoring group, reported that more than 1,540 people have been killed in Latakia, Tartous, Hama and Homs provinces.

They included 1,068 civilians, the vast majority of them Alawites who it said had died as a result of “killings, field executions and ethnic cleansing operations” by security personnel or pro-government fighters, as well as 230 security personnel and 250 pro-Assad fighters.

Security sources also told Reuters that 300 security personnel had been killed.

The BBC has been unable to independently verify the death tolls.

State news agency Sana said a mass grave containing the bodies of security personnel had been found in the former president’s hometown of Qardaha on Sunday. Turkey-based Syria TV cited residents as saying Assad loyalists had buried police killed in the recent fighting there.

UN human rights chief Volker Türk said his office had received “extremely disturbing reports of entire families, including women, children and hors de combat fighters, being killed”.

“There are reports of summary executions on a sectarian basis by unidentified perpetrators, by members of the caretaker authorities’ security forces, as well as by elements associated with the former government,” he added.

He demanded swift action by Syria’s interim authorities to protect civilians and hold those responsible for the killings and other violations to be held to account.