Syria's interim president Ahmed al-Sharaa has issued a plea for peace as the country is gripped by some of the worst violence in more than a decade and serious allegations are levelled at some of his supporters.
Human rights monitors reported hundreds of civilians had been killed in the country's western coastal regions in recent days, during intense clashes between pro-government forces and fighters said to be loyal to the former Assad regime.
Syrian government security forces and fighters loyal to Hayat Tahrir al-Sham (HTS), the al-Sharaa-led rebels who toppled the brutal Assad regime late last year, have been accused of carrying out revenge killings and executions against members of Syria's Alawite minority.
While not specifically mentioning the allegations levelled at his supporters, the Syrian leader issued a call for calm in an address to worshippers at a Damascus mosque on Sunday.
"What is happening in the country is a challenge and is expected," he said.
"We must maintain national unity and civil peace in the country as much as we can.
"We are able to live together in this country."
Fighting in the western provinces of Latakia and Tartus intensified late last week after Assad loyalists launched a series of attacks on government infrastructure.
The executive director of the Syrian Network for Human Rights (SNHR), Fadel Abdul Ghany, said there was evidence of Russian and Iranian involvement in the attacks.
"We have an indication that those happened in cooperation with Hmeimim (air) base, which is controlled by Russia.
"Leaked records released from some Assad remnants declare that there was a coordination between them.
"After those attacks, lots of Iranian media also highlight those attacks and there was a mobilisation behind those attacks."
Former president Bashar al-Assad, who sought asylum in Russia after he was ousted from power, belongs to Syria's Alawite community.
It makes up around 10 per cent of the country's population.
Syrian authorities have blamed alleged revenge killings on armed militia who had come to the support of government forces, who took out grievances against the former Assad regime on Alawite community members.
War monitors detail civilian death toll amid fighting
There are differing reports of the number of fatalities during the fighting.
On Saturday, the UK-based Syrian Human Rights Observatory said 745 civilians had been killed in the country's west.
The Syrian Network for Human Rights (SNHR) said non-state armed groups, the pro-Assad fighters, had killed 148 civilians.
SNHR said the nation's security forces and its affiliated groups had killed at least 327 civilians and disarmed militants.
The Syrian presidency on Sunday announced an independent committee would be established to investigate what had happened in the country's west.
It followed calls for action by the United Nations.
"The caretaker authorities' announcements of their intention to respect the law must be followed by swift actions to protect Syrians, including by taking all necessary measures to prevent any violations and abuses and achieve accountability when these occur," UN High Commissioner for Human Rights Volker Turk said in a statement.
The United States also joined criticism of the attacks.
"The United States condemns the radical Islamist terrorists, including foreign jihadis, that murdered people in western Syria in recent days," Secretary of State Marco Rubio said in a statement.
