BEIRUT — In a brazen assault near the Syrian capital, Islamic State militants abducted 300 cement workers and contractors from their workplace northeast of Damascus on Thursday, as fighting against the extremist group raged in the country's north ahead of a new round of peace talks.
In a blow to the Islamic militants, however, rebel fighters wrested control of a northern border town, potentially undermining IS supply lines across the border with Turkey and endangering one of its most important strongholds in Aleppo province.
The U.N. special envoy for Syria, meanwhile, said the next round of peace talks in Geneva was expected to start next week, around April 13, and would focus on a political process he hopes will lead to a "concrete or real beginning of a political transition."
Speaking to reporters in Geneva, Staffan de Mistura said he was encouraged by the fact that a partial cease-fire has largely held since going into effect Feb. 27, despite a series of worrisome incidents that continue to happen on a daily basis.
State TV said Thursday's mass abduction of workers from the al-Badia Cement Company took place in Dumeir, about 28 miles (45 kilometers) northeast of Damascus, where militants launched a surprise attack against government forces earlier this week. The state-run news agency SANA quoted a source in the company as saying there had been no success in efforts to establish contact with the workers.
At the factory headquarters in Damascus, a spokeswoman declined to discuss the kidnapped workers' fate, saying authorities had told the company to refrain from commenting on the abduction. "The situation is not easy at all," she told The Associated Press.
There was no formal responsibility claim for the kidnapping, but the IS-linked Aamaq agency posted a video showing the deserted cement factory, located near a military air base. The video showed what appeared to be a Syrian soldier lying on the ground, apparently dead. One militant is seen driving a truck, towing away a fork lift.
Islam Alloush a spokesman for the Army of Islam rebel group which has a strong presence in Dumeir, told the AP in an email that Islamic militants attacked five targets in the town, including other insurgents' positions near the airport. They also seized control of the factory, kidnapping hundreds of its workers.
He said his group had managed to secure some workers who got away, but the fate of the kidnapped workers was not known. Alloush added that the town is densely populated, making their ability to maneuver difficult.
The Britain-based Syrian Observatory for Human Rights, which monitors the Syria conflict, said earlier Thursday that contact had been lost with dozens of workers in Dumeir.
Mass abductions have taken place on occasion in Syria during the country's devastating civil war, now in its sixth year, most often targeting religious minorities or Syrian soldiers.
The abduction came as fighting raged in northern Syria, where Syrian opposition fighters made quick advances on strongholds of the Islamic State group, including al-Rai along the border with Turkey.
Opposition activists and a rebel group said the Free Syrian Army factions took over al-Rai, in northern Aleppo province, potentially severing one of the extremist group's most important crossings with Turkey.
FSA Division 99 said on its Facebook page that its fighters along with other groups were deployed inside the town and had taken down the IS flag and were combing the town. The IS-linked media agency Aamaq said at least 14 factions were fighting against IS in al-Rai.
The Observatory and the Local Coordination Committee activist group also said opposition forces were inside the town, driving out dozens of IS fighters.
If al-Rai falls, the rebels will be able to challenge the Islamic State's hold on al-Bab, the group's stronghold in Aleppo, activist Bahaa al-Halabi said.
In Geneva, de Mistura told reporters he was embarking on a Mideast tour that will take him to Damascus as well as the Iranian capital, Tehran, and possibly Amman, Jordan, in search of an understanding about what could be a framework of a political transition.
Two rounds of "proximity talks" involving Syrian opposition and government representatives in Geneva have ended without any progress on ways to end the war in Syria.
De Mistura said he would hold talks with senior Syrian officials in Damascus, but that he had not requested a meeting with President Bashar Assad.
Earlier Thursday, Jan Egeland, de Mistura's humanitarian aid adviser, said he was "disappointed" with recent efforts to get aid convoys into hard-to-reach and besieged areas, and called on the Syrian government to "live up to its promises."
Speaking in Geneva, Egeland said "April was supposed to be our best month" but that aid delivery is "not getting better and better, it's actually slowing down."
Humanitarian assistance is part of an international response to the country's crisis that also includes a U.S.-Russia-brokered cease-fire that has largely held over the last month.
El Deeb reported from Cairo.