Iranian troops have reportedly joined the fighting as the US is considering what to do.

Sunni militants yesterday, June 16, 2014, captured a town in the northwest of Iraq and other territory as US President, Barack Obama, was reportedly preparing to open dialogue with Iran on how to contain the advance of the insurgents, Fox News reported. The latest rebel victory was sequel to similar ones on Monday, June 15, 2014. Late last week, the army said volunteer fighters had helped it to halt the onslaught.

The Mayor of Tal Afar said the town, located about 418 km northwest of the capital, Baghdad, was seized before dawn by fighters from the Islamic State of Iraq and the Levant, ISIS. The town has a population of 200,000. A local resident, Hadeer al-Abadi, said the local security force fled before the rebels arrived, while local tribesmen who continued to fight later surrendered to the militants.

The Wall Street Journal yesterday reported that dialogue between the US and Iran on the crisis is expected to begin this week. Both sides have publicly pledged support to the beleaguered government of Iraq Prime Minister, Nouri al-Maliki, with the US dispatching an aircraft carrier to the region. Iran is said to have already deployed 500 elite troops to support the army, the CNN said yesterday.

Meanwhile, the Prime Minister of Iraq's Kurdistan region, Nechirvan Barzani, was in Iran yesterday for talks on efforts to thwart the Sunni insurgent offensive. A video posted on Internet appears to show the militants executing scores of captured soldiers as they pushed towards the capital. The massacre prompted evacuations by diplomats from Baghdad.

The speed of the Iraqi military's collapse in the face of relatively small numbers of militants has unnerved its Western allies. The US on June 15, 2014, sent nearly 100 troops to its Embassy in Baghdad and also moved some staff to other parts of the country.