Igor Kossov

Special for USA TODAY

HAMAM AL-ALIL, Iraq — When Islamic State militants swept across northern Iraq in 2014, some civilians welcomed them, some fled and others resigned themselves to living under their rule. But a few rose up to fight.

Members of these secret resistance groups, such as the "Mosul Battalions" and "Mim" factions, revealed to USA TODAY their efforts and details about the deaths of their members now that Iraqi forces are making slow but steady gains to oust the militants from Mosul, their last major stronghold in Iraq.

From before the start of the Mosul offensive last year until the present day, Iraqi troops have relied on a civilian resistance to pave the way. The resisters provide a large amount of military intelligence that helps save lives and lead to the capture and death of major commanders. Many civilians sowed chaos in Islamic State ranks by killing fighters, destroying checkpoints and sabotaging the militants' attempts at propaganda.

"It would be very difficult for a big group to fight" the Islamic State, also known as ISIS, and keep it a secret, said Salwan Hamis, 27, a former policeman in this town nearly 20 miles south of Mosul. He had attempted to join a resistance group in Mosul, but its members went into hiding shortly after he made contact with them.

Despite their caution, many paid with their lives for acts of rebellion as small as spraying anti-ISIS graffiti on walls and as important as assassinating ISIS fighters.

Hani Juma Muhammed Sultan, 48, is one such rebel honored as a hero in this town. He was gunned down by ISIS in 2016 after a lengthy battle.

The fisherman and former infantryman with the Iraqi military was no stranger to death threats from ISIS for working with American occupation forces. After watching ISIS fighters execute people in the streets, Sultan decided to do something about it, said his cousin, Theaa Shaher Ismail, 35. "He began to smuggle people out of (ISIS) territory" on his boat, Ismail said. "He was fearless."

Sultan knew the Tigris River very well and used it to his advantage. He was usually armed in case of surprises, according to Hamis, his friend and neighbor.

ISIS fighters aware of his activities started looking for Sultan. who evaded them by posing as an armed ISIS fighter. Sultan ambushed an unknown number by the Tigris, killed them and dumped their bodies in the water.

"He was making a revolution by himself," said his sister, Ghanya Juma Sultan, 51, who lives here. She described her brother as a "simple, straightforward" man doing what he believed was right. His family and some neighbors helped by giving him provisions and information on what was happening in the neighborhood.

"He came by all the time, telling us what he needed the next day," she said.

It's hard to say how many fighters Sultan had killed. Those interviewed put the number between 10 and 50. They all agree that ISIS saw him as a growing threat and hunted him in ever greater numbers. They also took out their frustrations by rounding up former police or military members and punishing or executing them in public.

Last June, the militants finally cornered Sultan in a building near the Tigris and killed him after a six-hour shootout. The fighters strung up his body in the middle of a road in Hamam al-Alil, according to shopkeepers who still work there.

"In the afternoon, they brought his body and hanged him up by the arms for two days," said Kharan Muneef, whose shop is on the same public square. "He killed ISIS, that's why they hanged him. Many people were hanged here for being against ISIS."

The fighters then tossed his body in a garbage pile — an act of major disrespect. Ismail and other family members came at night, recovered the body and buried him near one of the mass graves of other ISIS victims.

His actions inspired many people in this town and beyond. "Hani was a real man, it made me want to resist," Hamis said.

Another man honored for heroism was former Iraqi army colonel Muhammad Hasouni al-Juboori, who actively recruited resistance members in Hamam al-Alil and made a stand in his house against ISIS, killing several fighters before being gunned down, according to signs about him on the walls and several civilian interviews.

Perhaps drawing inspiration from his actions, a group of people burned down an outdoor club here where ISIS used to show propaganda films to civilians, including children. The ISIS sign was spray-painted over with red, the militant group's posters were ripped down, and a message was left: "Hawija Boys were here," referring to the town of Hawija in Kirkuk province, about 110 miles from Mosul.

Graffiti, sabotage and assassination against ISIS happened on a regular basis throughout the occupied cities and towns, according to those interviewed in Mosul, Hamam al-Alil and refugee camps. Most of the resistance members were known by the Arabic letter Mim, which stands for Muqawama, or "resistance."

The resistance ranged from individuals to small groups of friends or neighbors to associations of such small groups, occasionally referred to as Mosul Battalions.

Fudar Ahmad said her cousin who lived near an ISIS base in eastern Mosul broke into the base with a gun one night a year ago and killed a fighter before escaping. Ahmad never heard from her cousin again.

Mahmood Jassim, who volunteers at the Hamam al-Alil refugee camp, said there were a few groups in several Mosul neighborhoods that "everyone knew and talked about in secret." One of their exploits was sneaking up to an ISIS checkpoint at 3 a.m. and killing three fighters. The men were never caught, but ISIS responded by rounding up nearly 40 former military personnel and killing some of them.

Jassim said four of his friends used to go around at night spray-painting the letter Mim and obscene anti-ISIS messages on walls in Mosul. They were eventually discovered and shot execution-style in the street not far from Jassim's house.

One Mosul resident, who did not want to be named for fear of ISIS retaliation, said two men on motorbikes near his house gunned down notorious Islamic State executioner Abdul Aziz and two of his bodyguards. Another militant commander was shot dead in the same neighborhood by unknown assailants.

The man said he secretly provided information about ISIS positions to the U.S.-led coalition to use for airstrikes. Many residents of Mosul and nearby towns did the same, according to Emad Al Rashidi, adviser to the governor of Nineveh province, west of Mosul.

"There were people spying in Mosul on both sides" of the Tigris, he said. "Some of them were giving us coordinates of (ISIS) fighters. Others saved lives by preventing the bombing of civilians."

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