Iraqi government forces and Sunni militants are intensifying fighting in areas bordering Syria and Jordan.
A spokesperson for government forces said on Monday that they took back the border town of Walid from the Islamic State of Iraq and the Levant after fierce fighting.
But by Sunday the militant group had gained control of several border towns, including Qaim. They also captured Rutba, close to the border with Jordan.
They are trying to take control of cross-border routes in an apparent attempt to boost military capabilities with new weapons and fighters arriving from Syria.
But the militants' attacks on the capital Baghdad have been so far been stopped by air offensives by government forces.
Government forces have been carrying out military operations against the strategically important northern town of Tal Afar. Most parts of the town are under the militants' control.
The forces are preparing for a large-scale operation on major towns seized by the Sunni extremists.
The militants are drawing on Sunni Muslims' displeasure with the Shia-dominated government of Prime Minister Nuri al-Maliki to further expand its influence.
Jun. 23, 2014 - Updated 23:23 UTC