At least eight people were killed on Friday when an explosion struck a mosque used by Syria's Alawite minority in Homs, state media reported.
The blast, believed to be the first attack on a mosque since the overthrow last year of longtime leader Bashar Assad, himself an Alawite.
The blast was claimed by an Islamist militant group formed shortly after Assad's ouster.
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The Interior Ministry labeled the explosion at the Imam Ali Mosque in Homs, Syria's third‑largest city, a "terrorist bombing."
According to the Syrian Observatory for Human Rights, the mosque is attended primarily by members of the Alawite community.
State news agency SANA, citing a security source, reported that the blast was caused by explosives planted inside the mosque.
A government official said the devices detonated during the crowded Friday prayer service.
Photos released by SANA showed extensive destruction and bloodstains inside the prayer hall.
In addition to the eight fatalities, Health Ministry official Najib al‑Naasan told SANA that 18 people were injured.
The official said the figures were not final, indicating that the death toll could rise.
A local security official told SANA that investigators had not yet identified the attacker or confirmed any link to armed groups.
However, in a statement on Telegram, the Islamist militant group Saraya Ansar al-Sunna said later Friday that its fighters had "detonated a number of explosive devices" at the mosque.
The group was formed after the ouster of Assad, who is a member of the Alawite community.
Syria has faced multiple episodes of sectarian bloodshed since Assad was driven from power by a rebel offensive last year and replaced by a Sunni‑led interim government.
After his ouster, Assad fled to Russia, and since then, Alawite communities have faced a series of crackdowns.
The Syrian government has recently stepped up security campaigns against Assad loyalists and the self-declared Islamic State (IS) terrorist group.
On December 19, the United States launched strikes aimed at IS targets in Syria, not the Syrian state, in retaliation for an attack which killed two American servicemen and an interpreter a few days earlier.