At least 30 people have been killed in "arms market blast" in Syria by Sunni insurgents Islamic State of Iraq and the Levant (Isis), Syria TV has reported.
The claim comes shortly after Human Rights Watch and Amnesty International accused Isis of executing civilians, including children, in northern Syria.
Activists from the UK-based Syrian Observatory for Human Rights said on Friday that Isis forces have kidnapped thousands of people in Syria.
"[We] call for the release of more than 2,000 persons kidnapped by the Isis in Aleppo, al-Hasaka, al-Raqqa and Deir Izzor," the activists said. "The kidnapped include more than 500 Syrian Kurds as well as the prominent Human Rights activist Abdallah al-Khalil."
Isis insurgents made headlines worldwide when they took control of Mosul, Iraq's second largest city, and vowed to march on Baghdad.
The Iraqi government has asked for US support to fight back against Isis.
President Barack Obama is currently reviewing the options, but has ruled out sending troops back into Iraq.
Meanwhile, thousands of Iraqi civilians are joining government forces to fight against the insurgents.
IBTimes UK could not verify Syria TV's claim.
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