SULAIMANIYA, Iraq (Reuters) - If Islamic State is driven from its Iraqi stronghold of Mosul, it will switch tactics to wage an insurgency from mountains and deserts, a top Kurdish intelligence official has told Reuters.
Lahur Talabany, a senior figure in Kurdistan’s counter-terrorism efforts, also expressed concerns that another group similar to the Sunni Muslim Islamic State could emerge to menace Iraq again if political leaders fail to secure reconciliation between sects.
"Mosul will get taken ... I think it is the asymmetric warfare that we need to be worried about," he said.
"Our jobs will become much more difficult. The army will take a rest a little, but it will be the job of security forces that will become more difficult."
Talabany said there were signs that Islamic State planned to shelter in the Hamrin mountains in the northeast, which could serve as a base for attacks on several provinces.
He cited about five attacks on security forces in Diyala province in the last month.
"It is a very tough terrain. It is very difficult for the Iraqi military to control," said Talabany. "It’s a good hideout place and a place they could have access from province to province without getting detected."
The army, backed by Kurdish forces and Shi'ite militias operating in nearby towns and villages, has driven Islamic State from eastern Mosul after more than three months of battles.
Talabany said there would be more months of street-to-street and house-to-house fighting before the western side was taken, in effect putting an end to the group's self-proclaimed caliphate.
But he was cautious about the number of militants killed so far. There were en estimated 6,000 in Mosul at the start of the offensive and there is no evidence that anywhere close to that number have been killed, he said.
"We know some of these guys escaped. They are trying to send people out for the next phase, post-Mosul, to go into hiding and sleeper cells," said Talabany.
"You have to try and find them when they go underground, you have to try and flush out these sleeper cells. There will be unrest in this region for the next few years, definitely."
Talabany also said Iraq could not afford to underestimate Islamic State's charismatic leader, Abu Bakr al-Baghdadi.
"He is very wise. He is not using any kind of communications. He is in the desert area, coming and going between Syria and Iraq, we believe," he said.
"Their plans are to start up some sort of asymmetric warfare -- against the region and globally. Also, we will see lone-wolf attacks pop up here and there in the region."
In 2014, a few hundred Islamic State fighters seized control of Mosul in a few hours, partly because many fellow Sunnis welcomed them, complaining of abuses by the Shi'ite-dominated army and government in Baghdad.
Talabany urged political leaders to avoid making the same mistake again.
"... maybe not Daesh (Islamic State), but another group will pop up under a different name, a different scale. We have to be really careful," he said. "These next few years will be very difficult for us, politically."
So far, Iraq's sectarian violence has mostly pitted the majority Shi'ites against the Arab Sunnis, who dominated under Saddam Hussein.
But the Kurds have had their own tensions with Baghdad, mostly over oil resources and Kurdish dreams of independence, and Talabany suggested Iraq's internal hostilities could become far more complex unless dialogue was promoted on all sides.
"There is another threat out there that a lot of people are not seeing. We could clash with the (Shi'ite) militia in the future if there is no dialogue with Baghdad," he said.
In November, Shi'ite militias were transformed into a military corps that reports directly to the prime minister, who is a Shi’ite. This has caused concerns among Sunnis, including the Kurds, that they will be used to strengthen Shi’ite political domination.
"The militias are on our borders ... If there is disengagement from Baghdad and no dialogue, I believe they are much more difficult to control. They are not like the regular Iraqi army. I am worried that we could clash."
Editing by Kevin Liffey