Scorched-earth tactics cause deadly environmental damage, highlight IS group's battlefield losses and failure to sustain oil-fueled state.

Militants invade a gas compressor station and major oil field in Kirkuk province, killing police and oil workers and blowing up a storage tank.

After the loss of Q-West to Iraqi forces on Saturday, signs emerge that the IS group is crumbling south of Mosul, just as more American troops are announced for the fight.

The Islamic State group's fledgling oil sector in Iraq has been severed by the Iraqi military victory at the Qayarah air base south of Mosul.

Indigenous IS fighters in northern Diyala province are using insurgent tactics to threaten areas that have ostensibly been reclaimed by government-backed forces.

Prices of basic fuels have risen by up to 80 percent and quality has plummeted after a June 6 airstrike crippled IS’s import network of road tankers. US officials say the "best" third of the IS oil sector has now been destroyed.

A coordinated and well-planned IS offensive that killed the Tuz Khurmatu police chief shook the relatively secure frontline town, setting off alleged extrajudicial killings of prisoners nearby and a violent end to a tentative ceasefire between Kurdish and Turkomen forces.

Despite losing territory and facing crippling air strikes, militants still control some wellheads in Salahaddin province and are sneaking crude to Mosul, and on to Syria.

After weeks of stagnation, new reinforcements and intensified air strikes help the Iraqi Army liberate Nasir village and gain the initiative on the Ninewa front.

Workers at the Kurdistan oil project, operated by Russia's Gazprom Neft, have been targeted with land mines twice in the past week.