DAMASCUS: Syrian leader Ahmed Al-Sharaa vowed Monday that those involved in a “heinous” suicide attack on a Damascus church would face justice, as he called for unity in the diverse, multi-faith country.

The shooting and suicide bombing Sunday at the church in the working-class Dwelaa district of the Syrian capital killed 25 people and wounded 63, the health ministry said.

Syria’s interior ministry said Monday that authorities had arrested several suspects in connection with the suicide attack, with the minister saying the operation targeted cells affiliated with the Daesh group.

A ministry statement reported the arrest of “a number of criminals involved in the attack” during a security operation near Damascus, while Interior Minister Anas Khattab said the operation targeted “positions of terrorist cells linked to the Daesh group.”

Daesh has not yet claimed the attack.

“We promise... that we will work night and day, mobilizing all our specialized security agencies, to capture all those who participated in and planned this heinous crime and bring them to justice,” interim President Sharaa said in a statement.

The attack follows incidents of sectarian violence in recent months, with security one of the greatest challenges for the new authorities.

The attack “reminds us of the importance of solidarity, and unity of the government and the people in facing all that threatens our nation’s security and stability,” Sharaa said.

The spokesman for Antonio Guterres said the UN Secretary-General strongly condemned the attack and expressed his “deepest condolences” to the families of the victims and wishes a swift recovery to those injured.

He added that Guterres said that all perpetrators of terrorism must be held accountable, and called for a full investigation.

“The Secretary-General reaffirms the commitment of the United Nations to supporting the Syrian people in their pursuit of peace, dignity, and justice,” the statement added.

The attack was the first suicide bombing in a church in Syria since the country’s civil war erupted in 2011, according to the Syrian Observatory for Human Rights monitor.

It was also the first attack of its kind in the Syrian capital since Assad’s ouster.

A prayer service at the church is scheduled for 6:00 p.m. (1500 GMT).

Since the new authorities took power, the international community has repeatedly urged them to protect minorities and ensure their participation in Syria’s transition, particularly after the recent violence.

Interior ministry spokesman Noureddine Al-Baba said Sunday that “the security of places of worship is a red line, and all efforts will be made to ensure people’s freedom to perform their religious rites.”Daesh “aims to sow sectarian division and incite all components of Syrian society to take up arms, seeking to show that the Syrian state is unable to protect its communities and citizens,” he told a press conference.

The top cleric of Syria’s Sunni Muslim majority, Grand Mufti Osama Al-Rifai, condemned acts of violence and terrorism in a statement Monday.

“We express our complete rejection of targeting places of worship and terrorizing believers,” he said.

Foreign condemnation of the attack continued to roll in on Monday.

President Recep Tayyip Erdogan said Turkiye would not allow extremists to drag Syria back into chaos and instability, vowing that Turkiye would “continue to support the Syrian government’s fight against terrorism.”

Turkiye, which is close to the new authorities, has repeatedly offered its operational and military support to fight Daesh and other militant threats.

French President Emmanuel Macron also denounced the “horrible” attack, while the EU said it “stands in solidarity” with Syria in combating ethnic and religious violence.

“It is a grave reminder of the need to intensify efforts against the terrorist threat and to ensure the enduring defeat of Daesh and other terrorist organizations,” spokesperson Anouar El Anouni said.

Greece’s Prime Minister Kyriakos Mitsotakis expressed anger after the attack on the Greek Orthodox Church, calling on the new authorities “to take concrete measures to protect all ethnic and religious minorities.”

Syria’s Christian community has shrunk from around one million before the war to fewer than 300,000 due to waves of displacement and emigration.

Daesh seized large swathes of Syrian and Iraqi territory in the early years of the civil war, declaring a cross-border “caliphate” in 2014.

The militants were territorially defeated in Syria 2019 but have maintained a presence, particularly in the country’s vast desert.