Iraqi security forces and pro-government fighters on Sunday retook areas from jihadists near the Iranian border in an operation that left 20 Kurdish troops dead, security officials said.

The assault, launched early Sunday northeast of Baghdad in Diyala province, is the latest in a series of drives that have seen some territory lost to a sweeping June offensive by the Islamic State group being regained.

"Army and police and (militia) forces attacked from the southern and western sides of the Jalawla and Saadiyah (areas), while (Kurdish) peshmerga forces attacked from the northern and eastern sides of Saadiyah," Staff General Abdulamir al-Zaidi told AFP.

Accounts differed as to the extent of the gains in the two areas, with some sources saying they had been retaken and others reporting parts were still outside government control.

"The number of peshmerga killed is 20 and more than 40 were wounded during clashes against (IS) and by bombs at the entrance of Jalawla, inside Jalawla and in Saadiyah," peshmerga commander Mahmud Singawi told AFP.

Karim al-Nuri, a senior commander in the Badr militia, which took part in the operation, had earlier said bombs killed 12 members of the anti-IS forces.

He did not specify whether those killed were from the government security forces, Shiite militiamen, tribesmen or Kurdish fighters.

Explosive devices hidden beside or under roads and planted in buildings are a hallmark of IS, taking a toll on its enemies even after it withdraws or is forced out of an area.

An army brigadier general said Saadiyah and Jalawla were "the main centres of support for (IS) militants", whom security forces are seeking to isolate in the nearby Hamreen mountains.

The two areas are also important because of their proximity to the autonomous Kurdish region, which is battling the jihadists, and to the border with neighbouring Iran, which is also helping Iraqi forces.

Sunday's operation came on the heels of another that saw the strategic northern town of Baiji retaken from the militants and a months-long siege of Iraq's largest oil refinery broken.

Security forces and pro-government fighters also retook the Jurf al-Sakhr area south of Baghdad, which had posed a threat to both the capital and the Shiite shrine city of Karbala, which millions of pilgrims visit each year.

However, the militants sill hold large areas of the country, including the key cities of Mosul, Tikrit and Fallujah.

IS spearheaded a major offensive in June that overran much of Iraq's Sunni Arab heartland, sweeping security forces aside.

Backed by a US-led campaign of air strikes and by international advisers, Shiite militiamen and Sunni tribesmen, they are now performing better, but still face major challenges in the battle against IS.

Iraq sentences Sunni ex-MP to death for murder
Baghdad (AFP) Nov 23, 2014 - An Iraqi court sentenced former Sunni MP Ahmed al-Alwani to death on Sunday for murder, a verdict that could damage Baghdad's ties with a powerful tribe that is battling jihadists.

"The central criminal court sentenced Ahmed al-Alwani to death... for his killing of two soldiers," judicial spokesman Abdelsattar Bayraqdar told AFP, without saying when the murders took place.

He has a month to appeal the decision, Bayraqdar said.

Alwani is a member of the Albu Alwan tribe, members of which are fighting against the Islamic State (IS) jihadist group in the Ramadi area of Anbar province, a key front in the war against IS, which has seized key parts of Iraq since June.

Sheikh Omar al-Alwani, a leader of the Albu Alwan, said that any decision about Alwani should be put on hold and that the verdict could harm the fight against IS.

"All the Albu Alwan tribe is standing against (IS) on the side of the government," but "half of the Albu Alwan fighters will withdraw if they actually executed Alwani in these circumstances," the sheikh said, adding that even the former MP's guards were fighting against IS.

He said the government should wait until the fighting is over and IS defeated, then "take any decision it considers appropriate."

Illustrating their importance, the US Department of Defence has requested that Congress authorise $18.5 million in arms, ammunition and other equipment for tribes in Anbar and a further $5.5 million in contingency funding.

The gear includes 5,000 assault rifles, 12,000 grenades, 150 heavy machineguns, 50 82mm mortars and other items, according to a document outlining the request.

- Tribal support 'critical' -

"Failure to equip these forces mean a less effective armed opposition to counter the Islamic State," it said.

"Engagement from Sunni tribes is critical to the long-term defeat" of IS, the document said.

The arrest of Alwani, a prominent supporter of a now-collapsed Sunni Arab anti-government protest movement, was one of the factors that sent Anbar province spiralling into chaos.

He was detained during a raid on his house in late December 2013 that killed his brother Ali and five guards, inflaming Sunni Arab anger with the Shiite-led government, which many Sunnis view as having marginalised and unjustly targeted their community.

The defence ministry said at the time that one security forces member was also killed and five were wounded in the raid.

It said Ali was the target of the raid, but that both brothers and the guards opened fire when security forces arrived.

Ahmed had parliamentary immunity, but the constitution permits MPs to be arrested without their immunity being waived in cases of serious crime.

Just days after the raid, security forces demolished the country's main Sunni anti-government protest camp near Anbar capital Ramadi, setting off a series of events that led to the government losing control of parts of that city and all of Fallujah, farther east.

Almost 11 months later, Fallujah is still entirely out of Baghdad's control and is now a stronghold of the IS, while security forces and allied tribesmen are still battling for control of Ramadi.