Sunni militants have seized the northern Iraqi city of Tal Afar, officials and residents say.

Militants led by ISIS - the Islamic State in Iraq and the Levant - captured key cities including Mosul and Tikrit last week, but some towns were retaken.

UN human rights chief Navi Pillay said the "apparently systematic series of executions [of non-combatants] almost certainly amounted to war crimes".

The US earlier announced it might use drone strikes to halt the ISIS advance.

"They're not the whole answer, but they may well be one of the options that are important," said US Secretary of State John Kerry.
Iranian co-operation?

The Pentagon said US officials were also open to holding direct talks with Iran over Iraq, but there was "no plan to co-ordinate military activity" between the two countries.

Iranian President Hassan Rouhani earlier said he would consider co-operation if the US took action.

The USS George HW Bush aircraft carrier has already been deployed to the Gulf, accompanied by two more warships. But Washington says no US troops will be deployed on the ground.

Britain reiterated on Monday that it had no plans for military intervention in Iraq.

BBC