ISIS seizes another Iraqi city amid claims it massacred Iraqi troops

Tal Afar, near Mosul, fell after heavy fighting between ISIS militants and Iraqi troops. ISIS has instituted brutal law in the areas of the north it now dominates.

The jihadi army sweeping across Iraq seized another city in the northwest overnight, amid claims that the group has massacred some 1,700 Iraqi troops captured in Tikrit.

The Islamic State of Iraq and the Levant, also known as ISIS, overran the city of Tal Afar, just west of Mosul, last night after heavy fighting on Sunday. Reuters reports that before it fell, the mostly ethnic-Turkmen city had been defended by one of the few Iraqi units in the north not to flee in the face of ISIS' advance.

"The city was overrun by militants. Severe fighting took place, and many people were killed. Shi'ite families have fled to the west and Sunni families have fled to the east," said a city official who asked not to be identified.

Tal Afar is a short drive west from Mosul, the north's main city, which [ISIS] seized last week at the start of a drive that has plunged the country into the worst crisis since U.S. troops withdrew in 2011.

Tal Afar is just the latest city to fall in ISIS' lightning advance in Iraq. After seizing Mosul last week, the militant army rapidly expanded its zone of control southward and eastward, and now controls much of the north of the country between Baghdad and the largely autonomous Kurdish regions in the northeast.

The Guardian's Martin Chulov notes that Tal Afar's fall has no real military significance. "The north of the country and the centre has, by and large, been taken by Isis," he says. "If they take another town or village in the centre it is not going to change anything."

He adds that Baghdad is the big prize, but does not see ISIS as being able to take the city. "They [Isis] are a classic insurgent group, they are very capable, extremely dangerous. But to storm a city like Baghdad, which would be heavily defended by what remains of Maliki's military and irregulars is a very different matter."

ISIS says it has already begun implementing its own brutal law in the regions it has seized. According to claims and photos the group published on Twitter, it has killed 1,700 Iraqi troops the group captured in the city of Tikrit, reports euronews. The gruesome photos show militants lining up and executing dozens of men by firing squad. ISIS' claims, published on Friday on an account that has since been taken down by Twitter, could not be independently verified, but euronews notes that refugees from the city do confirm having seen the bodies of executed Iraqi soldiers.

The US condemned the attack, reports Agence France-Presse, but at present it is unclear whether the US or other Western nations will be willing to enter the fray. The Christian Science Monitor reported over the weekend that three US Navy warships, including the aircraft carrier George H.W. Bush, are en route to the Persian Gulf "should military options be required to protect American lives, citizens and interests in Iraq," according to the Pentagon. But the US so far has ruled out direct military participation against ISIS.

So too has Britain ruled out boots on the ground, reports the Press Association, despite public calls by ex-Prime Minister Tony Blair in the press over the weekend. "We're not planning a military intervention by the UK in this situation," Foreign Secretary William Hague told the BBC on Sunday.

But the US is considering turning to an unusual partner to deal with ISIS: Iran. The Monitor reported last week that the crisis could bring unusual cooperation between the two countries. And a senior US official told Reuters on Sunday that Washington is considering contacting Tehran about how to aid Baghdad. Iran is an ally of both Iraq and Syria, and although the US is ostensibly aligned against Iran and the regime of Syrian President Bashar al-Assad, ISIS is widely perceived as a greater threat, even among US hawks. As Sen. Lindsey Graham (R) of South Carolina told CNN on Sunday, "Why did we deal with Stalin? Because he was not as bad as Hitler."