By Stephen Kalin

MOSUL (Reuters) – Iraqi forces faced further pockets of resistance from Islamic State militants in Mosul’s Old City on Friday, four days after the prime minister declared victory.

Iraqi army helicopters flew overhead and explosions could be heard, residents said, while videos of alleged revenge attacks against people detained during the retaking of Mosul underlined future security challenges.

“Three mortars landed on our district,” a resident of Faysaliya, in east Mosul, just across the Tigris river, said by telephone.

A few hundred Islamic State insurgents swept into Mosul three years ago, imposed a reign of terror after the Iraqi army collapsed and declared a caliphate spanning Iraqi and Syrian territory seized in a shock offensive.

The victory of U.S.-backed Iraq forces in Mosul marked the biggest defeat for Islamic State, which is under siege in the eastern Syrian city of Raqqa, its operational base.

Even though the Sunni Muslim group’s caliphate is now crumbling, it is expected to revert to an insurgency and keep carrying out attacks in the Middle East and West.

Securing long-term peace in Iraq will not be easy.

Prime Minister Haider al-Abadi faces the challenge of preventing revenge killings that could create more instability, along with sectarian tensions and ethnic strife that have dogged Iraq since a U.S.-led invasion toppled Saddam Hussein in 2003.

Grand Ayatollah Ali al-Sistani, the country’s top Shi’ite Muslim cleric, urged Iraqis to avoid violence and sectarianism in his first Friday sermon since the proclamation of victory in Mosul, Iraq’s second largest city.

On Thursday, Human Rights Watch said it had used satellite imagery to verify that a video published on Facebook on Tuesday, showing armed men in military uniforms beating a detainee before throwing him from a height and then shooting at him, had been filmed in west Mosul.

The footage shows the men shooting at the body of another man already lying at the bottom of the perch. Reuters could not independently verify the footage.

Iraq’s joint operations command said the allegations were being looked at closely and if any violations were found, those responsible would be held accountable. It also said that the videos could have been fabricated.

Three other videos posted this week by the same account appear to show members of various Iraqi security forces beating men wearing ordinary clothes. Reuters could not independently verify the footage.

(Writing by Michael Georgy; Editing by Mark Heinrich)

MOSUL, Iraq (Reuters) – Iraqi forces clashed with Islamic State militants holding out in Mosul’s Old City on Wednesday, more than 36 hours after Baghdad declared victory over the jihadists in what they had made the de facto Iraqi capital of their self-declared caliphate.

Prime Minister Haider al-Abadi’s victory announcement signaled the biggest defeat for the hardline Sunni group since its lightning sweep through northern Iraq three years ago. But pockets of Mosul remain insecure and the city has been heavily damaged by nearly nine months of grueling urban combat.

About 900,000 people fled the fighting, with more than a third sheltered in camps outside Iraq’s second largest city and the rest living with family and friends in other neighborhoods.

Civilian activity has quickly returned to much of Mosul and work to repair damaged homes and infrastructure is underway, but authorities have not prepared a post-battle plan for governance and security in the city, officials say.

Iraqi forces exchanged gunfire with the militants in their final Mosul redoubt just before midnight and into the morning hours, three residents living just across the Tigris River from the area told Reuters.

Army helicopters strafed the Old City and columns of smoke rose into the air, though it was unclear if these came from controlled explosions or from bombs set off by Islamic State, the residents said by phone.

“We still live in an atmosphere of war despite the victory announcement two days ago,” said Fahd Ghanim, 45. Another resident said the blasts shook the ground around half a kilometer away.

An Iraqi military official attributed the activity to “clearing operations”.

“There are Daesh (fighters) hiding in different places,” he said, using an acronym for Islamic State. “They disappear here and pop up there, then we target them.”

Media access to the area has been heavily restricted since Abadi claimed victory on Monday, hailing “the collapse of the terrorist state”.

Footage released by the Islamic State news agency Amaq entitled “Fighting till the last gasp” and allegedly filmed in Mosul’s Maydan district showed militants mixed in with civilians and unidentified corpses lying amid the rubble of an urban battlefield. Reuters could not authenticate the video.

ASYMMETRIC ATTACKS

The Iraqi official declined to estimate the number of militants or civilians remaining in the Old City, but the top U.S. general in Iraq said on Tuesday that as many as a couple of hundred IS insurgents could still be in Mosul.

“There are bypassed holdouts. We haven’t cleared every building in this city the size of Philadelphia. That’s going to have to be done, and there are also hidden IEDs (improvised explosive devices),” Lieutenant General Stephen Townsend told reporters. “There are still going to be losses from the Iraqi security forces as they continue to secure Mosul.”

The U.S.-led coalition said it had conducted three air strikes on IS in the Mosul area on Tuesday, targeting militants, machine-gun emplacements and rocket-propelled grenade systems.

South of the city, Iraqi security forces repelled an IS attack launched from western desert areas on the village of al-Jaran, a tribal fighter said.

Reinforcements also arrived to help government forces oustmilitants armed with machine guns and mortars from the village of Imam Gharbi, further to the south. IS had taken around 75 percent of the village since storming it last week.

These are the kind of asymmetric, guerrilla-style strikes Islamic State is expected to concentrate on now as U.S.-backed Iraqi forces regain control over cities the group captured during its shock 2014 offensive.

Another attack on a border guard convoy in western Anbar province, near the Syrian border, killed two soldiers and wounded four on Tuesday, military sources said.

Separately, 28 Sunni Muslim civilians were kidnapped in the Iskandariya district south of Baghdad this week and 20 of them were found dead later, a police officer told Reuters.

Suspects detained by the authorities said they belonged to the Shi’ite Muslim Asaib Ahl al-Haq militia. A Baghdad-based spokesman for the group, whose fighters are taking part in the Shi’ite-led government’s campaign against Islamic State, said he had no knowledge of the incident.

The government’s victory in Mosul may rekindle revenge attacks and fresh violence between Sunnis and Shi’ites, a sectarian divide that tipped Iraq into civil war after the U.S.-led invasion that toppled Saddam Hussein in 2003.

(Reporting by Stephen Kalin; editing by Michael Georgy and Mark Heinrich)

By Ghazwan Hassan

TIKRIT, Iraq (Reuters) – Islamic State has captured most of a village south of Mosul despite losing control of its stronghold in the city, an Iraqi army officer and residents said, deploying guerrilla-style tactics as its self-proclaimed caliphate crumbles.

Prime Minister Haider al-Abadi declared victory over Islamic State in Mosul on Monday, marking the biggest defeat for the hardline Sunni group since its lightning sweep through northern Iraq three years ago.

But the militants, armed with machine guns and mortars, have now seized more than 75 percent of Imam Gharbi, a village on the western bank of the Tigris river some 70 km (44 miles) south of Mosul, and reinforcements are expected, the Iraqi army officer said.

Islamic State launched its attack on Imam Gharbi last week, in the kind of strike it is expected to deploy now as U.S.-backed Iraqi forces regain control over cities the group captured during its shock 2014 offensive.

Mosul resident Hind Mahmoud said by telephone that she had heard exchanges of gunfire in the Old City and seen an Iraqi army helicopter firing on Islamic State militants on Tuesday.

Stripped of Mosul, Islamic State’s dominion in Iraq will be reduced to mainly rural, desert areas west and south of the city.

Islamic State also faces pressure in its operational base in the Syrian city of Raqqa, where U.S.-backed Syrian Kurdish and Arab forces have seized territory on three sides of the city.

The campaign to retake Mosul from the militants was launched last October by a 100,000-strong alliance of Iraqi government units, Kurdish Peshmerga fighters and Shi’ite militias, with a U.S.-led coalition providing key air and ground support.

Abadi’s government in Iraq now faces a difficult task managing the sectarian tensions which enabled Islamic State to gain supporters in the country among fellow Sunnis, who say they were marginalized by the Shi’ite-led government.

The U.S.-led coalition warned that victory in Mosul did not mark the end of the group’s global threat.

“Now it is time for all Iraqis to unite to ensure ISIS (Islamic State) is defeated across the rest of Iraq and that the conditions that led to the rise of ISIS in Iraq are not allowed to return again,” Lieutenant General Stephen J. Townsend said in a statement.

(Writing by Michael Georgy; Editing by Gareth Jones)