ISIS take 700 hostages including US and European nationals and will 'execute 10 people a day', Putin says

ISIS has kidnapped 700 people including several US and European nationals in Syria and will "execute 10 people every day" unless its demands are met, Vladimir Putin said on Thursday.

The militant group has already killed a number of hostages and warned of daily executions to come, the Russian president said.

He did not specify the group's exact demands, Reuters reports.

ISIS fighters attacked a refugee camp in an area controlled by US-backed forces last week, kidnapping some 130 families, according to local media.

Images have emerged allegedly showing ISIS fighters attacking and kidnapping fighters from the US-backed Syrian Democratic Forces in the same area the day before.

Speaking to the Valdai discussion forum in Sochi, a Russian city by the Black Sea, Mr Putin said: "They have issued ultimatums, specific demands and warned that if these ultimatums are not met they will execute 10 people every day.

"The day before yesterday they executed 10 people."

In Washington, the US military cast doubt on Putin's claims.

Commander Sean Robertson, a Pentagon spokesman, said: "While we have confirmed that there was an attack on an IDP (internally displaced persons) camp near (Deir-al Zor) last week, we have no information supporting the large number of hostages alleged by President Putin and we are sceptical of its accuracy.

"We are also unaware of any U.S. nationals located in that camp."

A representative of The Syrian Observatory for Human Rights said the estimated number of detainees held by ISIS was 300.

These included 90 women, some of whom are the widows of IS members killed earlier in the Syrian war.

They said: "The real number of abductees held by the 'Islamic State' organisation is estimated by 300 persons including 90 women."

ISIS was expanding its control in territory on the left bank of the River Euphrates controlled by US and US-backed forces, the Russian president said.

On Wednesday, the TASS news agency reported ISIS militants had taken around 700 hostages in Syria's Deir-al Zor province.

This was after they attacked a refugee camp in an area controlled by US-backed forces on October 13.

The agency reported the militants had kidnapped around 130 families and taken them to the city of Hajin.

The Syrian Democratic Forces said that its fighters had engaged in combat with ISIS on October 13 and killed 20 members of the group.

This was as, according to a statement, militants from ISIS descended to "target the camp for the displaced people".

The group added that "special units of our forces carried out an urgent evacuation of civilians from the camp to areas away from the engagements field".

It said the fighting lasted many hours before some ISIS members fled with hostages and some of the Syrian Democratic Forces troops were "martyred" as they died in the incident.