BAGHDAD, Iraq - The Islamic State group is digging in hard in parts of Iraq, launching a string of large-scale suicide attacks, and prompting fears of many more months of heavy fighting even as the government in Baghdad celebrates the reported liberation of Ramadi.

The fighting has been concentrated around Fallujah and the surrounding desert, but it has also embroiled towns and villages along the road west to Samarra, the site of one of Shia Islam’s holiest sites, towards the strategic oil refinery town of Baiji.

After months of fighting, the Iraqi government announced last month that its security forces had liberated Ramadi, the provincial capital of Anbar which had been occupied by IS since May 2015.

With Haider al-Abadi, the Iraqi prime minister, attending a ceremony on 29 December to raise the Iraqi flag, the city’s recapture was hailed as a morale boost for the Iraqi people and proof of the ability of a range of Iraqi armed groups including government security forces and Shia-dominated militias to work together to push IS back.

But IS is refusing to give up, with one military commander telling Middle East Eye that even the centre of Ramadi was not yet completely under government control.

Since the city was announced liberated, Iraqi troops and supporting groups have faced a relentless tirade of car bombs, suicide bombers and mortar attacks.

"We have almost finished the liberation of central Ramadi,” Major General Sami al-A'aridhi, the commander of an Iraqi counter-terrorism unit, told MEE by phone.

“We still have just two goals which we believe are almost in our hands, and then we can definitely say the centre is totally under our control.”

According to A'aridhi, the last-ditch IS drive on the town has a two-pronged objective of throwing a lifeline to its fighters left in the town, while also engaging the Iraqi forces ranged against them for long enough to allow it to regroup in Fallujah, 50km to the east.

A'aridhi said that Iraqi commanders were aware that IS fighters were withdrawing to Fallujah, but said no units would be redeployed from Ramadi until it was secure.

Fallujah, which is about halfway along the main highway connecting Ramadi to Baghdad, was the first major Iraqi town to fall to IS two years ago.

But concerns about IS cells infiltrating the suburbs of Baghdad, as well as the need to allow food and medical supplies to reach civilians still living in Fallujah, have allowed IS to retain control of the town, albeit loosely surrounded by Iraqi forces and supporting militias.

Fallujah back on frontline

Since the recapture of Ramadi, Fallujah has once again found itself on the frontline.

Already this month IS has hit an Iraqi army headquarters in Thirthar, 25km north of Fallujah. The attackers seized huge amounts of weapons and drove Iraqi forces westwards to Saqlawiya, raising fresh concerns about the security of the Thirthar dam, which serves as a flood control for Baghdad and which IS fighters briefly partially occupied last April.

The days-long attack was followed by similar incidents targeting Iraqi troops deployed in the sparsely populated and largely desert areas east of Ramadi and north towards Samarra which IS has long claimed as its territory.

"Daesh is fighting in a half circle around Thirthar Lake from the south [just north of Ramadi and Fallujah],” Abdulwahid Tuama, an independent Iraqi political analyst told MEE, using an Arabic acronym for IS.

“They have been attacking the Iraqi troops there to drive them away from this area and widen the gaps in Fallujah’s siege.”

Emad Bellow, a former military general and an independent military analyst, agrees.

"Fallujah is besieged and Daesh is keen to strengthen its forces there and attack the collar around it to delay the Iraqi forces from getting in and expand the areas under its control," Bellow told MEE.

As the main water source in largely arid western Iraq, the area around Thirthar Lake has seen some of the fiercest fighting.

Supply routes

The main roads connecting IS-held Deir Ezzor and Raqqa in Syria, which pass just west of the lake, are the main supply routes to Mosul, Iraq’s second city which has been under IS control since June 2014.

Tuama said an oil pipeline linking Baiji to Baghdad also ran through the region.

“These are important ground supply routes for IS and the Iraqi army,” he said. “There are trenches and caves which militants have been using for years as command headquarters and shelters."

Iraqi security authorities have been down playing recent IS attacks and have avoided mentioning their own casualty numbers, while also stressing that dozens of militants have been killed in recent clashes.

The US-led anti-IS military coalition, which has been backing government forces with airstrikes since 2014, claims that IS-controlled territory in Iraq has been reduced by 40 percent, although that figure is heavily contested.

Despite the ferocity and widespread nature of recent attacks and concerns that IS will continue resisting Iraqi efforts to push it back, analysts and military officials alike point out that the group is no longer making significant territorial gains.

Nonetheless, several areas from where IS was driven out last year are once again coming under pressure, with the fallout from the fall of Ramadi being felt more than 100km to the north in small towns and villages west of Samarra and as far away as Baiji.

Weak defences

Local officials have reported small attacks behind the frontlines including an attack by six suicide bombers on 3 January on a fortified military base at Spicher, in the east of the city of Tikrit, in which 15 police officers were killed and 22 injured.

Some military officials acknowledge that such attacks highlight the fragile security of supposedly liberated areas, as well-trained and equipped Shia militias are redeployed to join the fighting around Anbar.

"Daesh has exploited the weak defences of the Iraqi forces in these areas as it is a vast desert area and there are not enough troops to secure it," a senior Iraqi military officer, talking on condition of anonymity, told MEE.

"They (IS fighters) are very skilled when it comes to fighting in open areas like the desert as they know every inch there. They belong to the area, know the trenches there, the caves and the dirt roads, while the Iraqi soldiers have none of this knowledge," the officer said.

Shia militias have been working side by side with formal security forces to secure the road network between Baghdad and Baiji ever since the retreat of the Iraqi army towards Baghdad in the face of IS’s rapid advance through the west of the country in June 2014.

Since the start of the month, hundreds of fighters belonging to Saraya al-Salam, armed forces loyal to Shia cleric Muqtada al-Sadr, have been engaged in fierce fighting in the Thirthar desert, bidding to regain ground lost to IS outside Fallujah.

But some fear they are not well trained enough for the task and may not get the air support they need.

"The problem is the number of troops which are supposed to secure these areas. It's not enough, so the Iraqi security forces have been relying on the paramilitary troops to do this," Emad Bellow, a former general and an independent military analyst, told MEE.

Bellow said that paramilitary troops including Saray al-Salam lacked the military experience to build effective defences for the terrain and deploy their forces to cover themselves effectively.

"Daesh is looking to cut off the supply routes of the Iraqi army in these areas and maintain its routes, so they carry out these attacks and promote them as a victory," said Bellow.

"They (IS fighters) are targeting the irregular troops because they know how to play it with them and take advantage of their mistakes."