Islamic State Militants Pursued After Syria Prison Break

Days after the death of Islamic State’s leader, U.S.-backed Kurdish-led militias are hunting down fugitives involved in a northeast Syria prison break that the terrorist group launched last month to replenish its dwindling ranks.

Islamic State gunmen have appeared in the city of Hasakah more than two weeks after the prison break, showing how the Jan. 20 attack could have a lasting impact on the group’s ability to regenerate and terrorize the surrounding community. The assault on the prison was Islamic State’s worst attack in Syria in at least three years, resulting in a weeklong siege and gunbattles that left nearly 500 people dead.

The prison break was among the last acts directed by Islamic State’s leader, Abu Ibrahim al-Hashimi al-Qurayshi, who detonated explosives that killed him and his family during a U.S. Special Forces raid in northwestern Syria last Thursday.

Qurayshi was concerned about a lack of fighting manpower in recent months, said intelligence officials with the U.S., Iraq and a European country. The United Nations estimates ISIS retains at least 6,000 fighters across Iraq and Syria, where it is forming cells and training operatives to launch attacks.

But with most of Islamic State’s fighters in prison or in hiding, much of its force was made up of women who had escaped from Syria’s displacement camps for families, the officials said.

Umm Hussein, 54 years old, who lives near the prison, said she fled during the fighting and returned home Friday to change the locks before moving back. After hearing a noise inside, she swung open a door to find two men in the loosefitting, black and brown clothes of Islamic State, running from her kitchen to the living room.

She ran outside and called for help. Neighbors crowded outside the house as security forces arrived, grabbed the two men and drove them away in trucks.

For Umm Hussein, it was a surreal repeat of the first night of the prison break, when Islamic State members, including one still wearing an orange prison jumpsuit, barged into her house looking for a change of clothes before they fled into the night.

“I’m afraid. I’m worried. That’s all I feel,” she said.

The ongoing hunt for escaped prisoners shows how the prison break may have succeeded to a degree beyond that acknowledged by American officials and their local partners. The Syrian Democratic Forces, a Kurdish-dominated militia that controls northeastern Syria with U.S. backing, has yet to disclose how many prisoners remain on the run.

The SDF said it killed 374 Islamic State members and recaptured at least 1,100 prisoners. Between 3,500 and 5,000 prisoners were held before the attack.

As the manhunt continues, the SDF has imposed a 6 p.m. curfew and deployed additional security forces, with extra trucks and gunmen in balaclavas posted in public squares as far away as Raqqa, 115 miles west of Hasakah.

Islamic State has used prison breaks to bolster its ranks ever since the group grew out of the insurgency against the U.S.-led occupation of Iraq after 2003.

The attack in Syria last month triggered alarms in Iraq, where officials worried the Syria prison break could lead to a repeat of the mass breakout of jihadists at Abu Ghraib prison in July 2013, which became a pivotal moment in Islamic State’s rapid expansion the following year, an Iraqi official said.

Using informants on the ground, Iraqi intelligence intensified its efforts to track Qurayshi’s location in Idlib and passed their findings to counterterrorism officials in the U.S., said Iraqi and Western officials.

Western security officials say Islamic State’s next leader is likely to be from Iraq, the organization’s birthplace and the country where its cash reserves are hidden. Qurayshi and his predecessors were also Iraqi.

The Syria prison break itself was a powerful statement of Islamic State’s enduring abilities. Three suicide car bombs slammed into the prison. Inmates besieged their guards, beheading some of them, said Malak Maesh, 26, a guard who survived.

Prisoners poured into the surrounding area, confirming something Hasakah residents had long feared, that Islamic State members and informants had been hiding among them for months or even years.

Two families said Islamic State members, using help from local informants, were searching the city for local security forces and executing them, some by beheading.

On the night of Jan. 20, about 20 Islamic State men appeared at the door of Abdel Qader Azayzi, a 29-year-old mechanic living near the prison. With them was a man wearing a mask, guiding the militants as they hunted for security officers. The man knew him, Mr. Azayzi said.

“Leave them. These men work on cars,” the masked man said, referring to Mr. Azayzi and his brother.

Unsatisfied, the gunmen pushed their way into the house and began searching the men’s phones. On the phone of Mr. Azayzi’s young cousin, Ghassan, they found an image of him in military uniform. The men hauled Ghassan outside and shot him dead.

“We can’t sleep at night,” said Mr. Azayzi.

The attack put a spotlight on the U.S. partnership with the SDF, which the U.S. has backed in the fight against Islamic State since 2014.

“It shows limits of the SDF, including its intelligence gathering about communities where ISIS still operates and friction between local Arab communities and SDF leadership,” said Robert Ford, a former U.S. ambassador to Syria.

“Without reform of the SDF, ISIS will find a few recruits every week,” he said.

The SDF has rejected the assertion that it is to blame for Islamic State recruitment, and has argued that the world has given it the unfair burden of guarding thousands of members, affiliates, and their family members. Prisoners in the Hasakah prison had at least 20 different nationalities, officials say. Countries across the world have generally refused to accept the return of their citizens held in the facility.