At least 400 civilians have been kidnapped from the Syrian city of Deir al-Zor by Islamic State militants, the Syrian Observatory for Human Rights said on Sunday. According to Reuters, the monitoring group reported that the families of pro-government fighters were among those taken.

The eastern city (and province of the same name) is of tactical significance to ISIS, linking Raqqa, its de facto capital, with its territory in Iraq. From Reuters:

Syria’s state news agency SANA said earlier that at least 300 people, including women and children, had been killed during the attacks in Deir al-Zor, but it made no mention of people getting kidnapped.

Syria’s government condemned the killings which it described as a “horrific massacre against the residents of Begayliya in Deir al-Zor”.

A source close to the Syrian government side said on Saturday that some of those killed had been beheaded.

ISIS said its fighters launched several suicide bombings against regime forces in the city, Agence France-Presse reports, and had gained control of the northern suburb of Al-Baghaliyeh.

The London-based SOHR reported that at least 85 civilians and 50 government troops were killed in the fighting. At least 16 jihadis were also killed. Syrian government forces were reportedly supported by Russian airstrikes.

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