The Islamic State of Iraq and the Levant (ISIL) has beheaded two women and their husbands in eastern Syria's Deir Ezzor province, a monitoring group said.
The UK-based Syrian Observatory for Human Rights said on Tuesday that ISIL beheaded the couples after accusing them of using "magic for medicine".
It is not known what non-traditional health remedy the two couples had sought.
"It is the first time that the beheading of women, by the use of sword in public, has taken place in Syria," the Observatory's chief, Rami Abdel Rahman, told Al Jazeera.
Al Jazeera cannot confirm whether the executions represent the first time that women have been beheaded in Syria. Last year, ISIL reportedly beheaded at least three women who were Kurdish Peshmerga fighters in Kobane.
The more recent beheadings took place in the city of Deir Ezzor and the city of Mayadin. ISIL beheaded the first couple on Sunday and the second couple on Monday.
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ISIL reportedly covered up both women and beheaded them, with many people watching, the Observatory said.
The Observatory said earlier this week that it has documented 3,027 executions carried out by ISIL since the declaration of their 'caliphate', including those of 1,787 civilians, 74 of them children.
More than half of those executed were civilians and more than half of the executed civilians were members of the Sunni Shaitat tribe, which revolted against ISIL south of Deir Ezzor city in August 2014.
ISIL reportedly previously beheaded male British and American aid workers, American and Japanese journalists, Kurdish and Syrian soldiers.
With regard to women, the Observatory documented in late August in 2014, that ISIL gave its fighters 300 Yazidi women in Syria.
Source: Al Jazeera