The Security Council in an emergency session on Thursday condemned attacks by fighters from the "Islamic State" (IS) in northern Iraq, and called on the international community to support the country's government and population.

IS militants moved towards the Kurdish capital of Irbil on Thursday, seizing Iraq's main Christian city of Qaraqosh and forcing tens of thousands to flee.

"The members of the Security Council call on the international community to support the government and people of Iraq and to do all it can to help alleviate the suffering of the population affected by the current conflict in Iraq," said Britain's UN Ambassador Mark Lyall Grant, who is serving as the council's president for August.

The closed-door meeting of the 15-member council was held at France's request.

"It's quite clear that [IS] has expanded its attacks very widely into Kurdish areas," Grant told reporters. "There was a deep alarm in the Security Council about the speed of events."

Pentagon denies airstrikes

A Pentagon spokesman Rear Admiral John Kirby denied media reports that US warplanes had already bombed militant targets in Iraq.

The US has a diplomatic consul and military operations center in Irbil.

A spokesman for the Kurdish peshmerga force told the AFP news agency that US airstrikes had hit two IS targets in northern Iraq.

"F-16's first entered Iraqi airspace on a reconnaissance mission and are now targeting Daash (IS) in Gwer and the Sinjar region," Holgard Hekmat said at around 2100 UTC.

Hekmat said the bridge linking Mosul to Gwer, which he described as IS militants' "main supply line," had been hit. Gwer lies only 30 kilometers (20 miles) southeast of the main border checkpoint leading into the autonomous Kurdistan region.

US mulling action

Senior US officials told news agencies that the US was weighing its options on Iraq, including the first airstrikes in the country since the 2011 troop pullout.

However, White House spokesman Josh Earnest said any US military action would be "very limited in scope" and insisted the unrest in Iraq would be solved diplomatically, not militarily.

"The situation is nearing a humanitarian catastrophe," Earnest said. "We are gravely concerned for the (Iraqi people's) health and safety."

dr/av (AP, Reuters, AFP, dpa)