BEIRUT: Daesh (ISIS) militants staged a surprise attack early Tuesday at a crossing frequently used by Iraqi and Syrian civilians seeking safety in northeastern Syria, killing 46 people, mostly civilians, Kurdish officials and activists said.

The predawn attack took place after militants sneaked into the village of Rajm Sleibi, located along a front line that separates the Kurdish-controlled Hassakeh province from Daesh-held areas further south. Some militants reportedly blew themselves up at a Kurdish checkpoint while others attacked sleeping civilians in a nearby temporary camp sheltering hundreds of displaced people who fled Daesh-controlled territory.

The International Rescue Committee said thousands of people from the Iraqi city of Mosul have traveled west to the Sleibi crossing since October, often via smugglers. In a statement, it said several children were among the dead and wounded.

“It was three in the morning when Daesh came and started to shoot at people,” said Abdullah Khalef Hamid, an Iraqi refugee from Mosul, who said his mother-in-law was killed in Tuesday’s attack. “I was wounded and they thought I was dead so they left me. We were around 200 families, they left at sunrise.”

Redur Khalil, a spokesman for the main Kurdish fighting force in Syria, said the attack started with an early morning assault by Daesh militants on a checkpoint in Sleibi belonging to the Syrian Democratic Forces, a U.S.-backed and Kurdish-dominated force that fights Daesh.

The militants then “committed a massacre” against civilians as they sought to enter SDF-controlled territory, Khalil said.

Khalil told the Associated Press the attack came a few hours after Daesh suicide bombers dressed in civilian clothes sneaked into the town of Shaddadi and attacked SDF forces, triggering clashes that were ongoing.

Survivors from the attack on the camp said the militants arrived in four cars before shooting several people and kidnapping others.

“They were shouting ‘You are infidels and you are going toward the infidels,’” said Fatima, a displaced Syrian woman who asked that her last name not be used, fearing retribution. “They shot at the checkpoint and at the civilians there, and they dragged the youngsters and put them in the cars and drove them away,” she said.

Issam Amin, a media activist in Hassakeh, said the victims arriving at the city’s hospitals had stabbing and knife wounds. The Britain-based Syrian Observatory for Human Rights said Tuesday’s attack included suicide bombers and heavy clashes with the SDF. The Observatory put the death toll at 46, including 31 civilians, many of them Iraqi.

Daesh is under attack by an array of forces in Syria and Iraq. In Syria, the SDF is now fighting to recapture the town of Tabqa from Daesh.

The town is an important stronghold for the militants, located about 40 kilometers southeast of their de facto capital, the city of Raqqa. The SDF pushed the militants to northern neighborhoods of Tabqa, close to one of Syria’s largest dams, and Kurdish officials say the battle will be over soon. According to the Observatory, “the SDF is now in control of 90 percent of the city” after they allowed some Daesh fighters to withdraw east toward Raqqa.

In an online statement Tuesday, the SDF said clashes were ongoing in a final northern neighborhood, and that other Daesh militants had been squeezed onto the adjacent dam.

The group claimed responsibility for Tuesday’s attacks through its media arm, Amaq, saying its fighters attacked four Kurdish positions in the southern countryside of Hassakeh province. Rajm Sleibi lies about 30 kilometers south of the town of Al-Hawl, which houses a large refugee camp for civilians displaced from Syria and Iraq.

A Kurdish activist said it is the entry point to Hassakeh for Syrians civilians fleeing the eastern cities of Deir al-Zor and Raqqa, and those fleeing from Mosul and elsewhere in Iraq. Civilians initially spend about two weeks in Rajm Sleibi while they get security clearance from Kurdish authorities, and from there are taken then to Al-Hawl camp. The activist spoke on condition of anonymity, fearing for his safety. The camp is within the zone of influence of the SDF but not immediately protected by the forces.Tuesday’s fighting comes a day before the Syrian government and the opposition were scheduled to resume cease-fire talks in the Kazakh capital, Astana. A rebel delegation led by the Army of Islam faction leader Mohammad Alloush arrived in Astana for the fourth round of talks sponsored by regime supporters Russia and Iran along with rebel-backer Turkey. Yehya Aridi, an adviser to the main opposition High Negotiations Committee, told AFP the group will participate in the talks with “approximately” the same delegation as in previous rounds. Regime negotiator Bashar al-Jaafari will lead the Damascus delegation. U.N. envoy Staffan de Mistura will also take part in the talks that could pave the way for a new round of U.N.-brokered peace negotiations in Geneva this month, the U.N. said Monday.