Syria's conflict sent shocks throughout the Middle East on Wednesday, with militiamen in neighboring Lebanon saying they had taken more than three dozen Syrian nationals and a Turkish man hostage, while several regional governments urged their citizens to immediately leave Lebanon.
Inside Syria, government jets razed homes and reportedly killed nearly two dozen people in a rebel-held town in the country's north. In Geneva, a United Nations commission held Syria's government and affiliated militia responsible for crimes against humanity, including for an attack that left scores of villagers dead in May.
Shiite Muslim militiamen in Beirut, Lebanon's capital, said Wednesday they had taken some 40 people—Syrians and a Turkish national—into captivity since the previous day. Dressed in military fatigues and brandishing assault rifles, masked gunmen from Lebanon's powerful Meqdad family demanded the release of a kinsman they said had been snatched inside Syria on Monday by fighters from the rebel Free Syrian Army. The militia members vowed to target Qatari, Saudi and Turkish nationals as well.
"We have a very wide range of targets and we do not advise anyone to test us," one of the masked gunmen, who identified himself as a member of the Meqdad family's military wing, said in remarks broadcast on several Lebanese stations from the family compound in Beirut's southern suburb.
Syria's conflict, as the kidnappings attest, is increasingly splitting the region along sectarian lines.
Syria's embattled President Bashar al-Assad has surrounded himself primarily with members of his Alawite sect, an offshoot of Shiite Islam. Most Shiites in Lebanon support Mr. Assad. The Syrian president is opposed largely by Sunnis, the majority population in Syria. As the conflict has deepened, Sunni-majority neighbors, including Saudi Arabia, Qatar and Turkey, have supported Syria's rebels.
People familiar with the Meqdads characterized them as essentially a large family with guns, which has had a contentious history with the far more influential Shiite militia Hezbollah, as well as the Lebanese state. Regional governments appeared to take the group seriously. The Saudi Embassy in Beirut told its nationals to leave Lebanon immediately after the "public threats" against them. The United Arab Emirates and Qatar issued similar warnings, their state media reported.
Many Lebanese, meanwhile, watched with apprehension as the government and security forces made no apparent attempt to intervene as boasts of mass kidnappings were playing out on national television.
The country was further destabilized by news that Wednesday's Syrian government offensive against Azzaz, a northern Syrian town near Aleppo, struck a building where rebels have been holding 11 Lebanese Shiites who were kidnapped in Syria in May. After the attack, angry Lebanese in Beirut blocked the road to the airport, as they have done before to demand the release of their kidnapped relatives in Syria.
The strike on Azzaz leveled buildings and brought chaos to a town where rebel fighters had begun to experiment with self-governance after having proclaimed the territory liberated from government troops three weeks ago.
Syrian fighter jets conducted two bombing runs that sent civilians fleeing, said Associated Press reporters who witnessed the attack, adding that they saw at least eight dead, including a baby, and dozens wounded, most of them women and children. The Syrian Observatory for Human Rights, a U.K.-based group, gave a preliminary death toll of 23 people, and more than 200 injured.
A building housing the 11 Lebanese hostages was struck in the bombing, injuring two of them and leaving the fate of four unknown, said Louay Mokdad, a spokesman for the Free Syrian Army's higher military council. The four men who are unaccounted for are believed to be trapped under concrete rubble in the building's basement, where many of the men were seeking shelter, Mr. Mokdad said. The two injured were being treated at a nearby field hospital.
In recent weeks, the Lebanese men had made video and press statements—one broadcast live by a Lebanese station reporting from Azzaz last week—saying their Syrian captors were treating them well and they were all in good health.
The Azzaz attack came as a U.N. human-rights commission said government forces and pro-government militia had committed crimes against humanity—including murder, torture, sexual violence and war crimes—in Syria, and were responsible for the May 25 killings at Houla of over 100 Syrian civilians.
The report on the findings of the U.N. Independent International Commission of Inquiry on Syria between March and July is the first time a U.N. body concludes that the Syrian government has committed crimes against humanity, a charge that sets the stage for the potential trial of individuals at the International Criminal Court.
Antigovernment rebels have also committed "murder, extrajudicial killings and torture," the report by the commission said, adding: "These violations and abuses were not of the same gravity, frequency and scale as those committed by government forces and the Shabbiha," or pro-government militants.
The Lebanon kidnappings underscored the fragile balance in the country, where sectarian tensions are deep. The government is a delicate and often dysfunctional offset between rival camps—with parties allied with the Shiite Hezbollah militia and political party dominating government posts, and opposition Sunni and Christian factions controlling some institutions. Feudal-like political leaders rule local areas. The country's army, under the 1989 accord that ended Lebanon's 15-year civil war, is supposed to maintain neutrality.
Lebanon's divisions are so deep that any intervention by the country's security forces risks making matters worse, according to Khaldoun al-Charif, an adviser to Prime Minister Najib Mikati. He said calls were being made to all political faction leaders to contain the crisis.
"The role of the government is to try to preserve the balance as much as possible to keep the country from imploding," said Mr. Charif.
But several observers and officials, including those allied with anti-Syrian factions in government, saw Wednesday's events as a deliberate attempt by the Assad regime and its allies in Lebanon to widen the sphere of the conflict to deflect the increasing international pressure on Damascus.
"This is an attempt to plant Syria's problems in Lebanon," said Khaled Daher, a Lebanese lawmaker with the anti-Syrian March 14 bloc.
Questions surround the clan that took responsibility for the recent kidnappings. The Meqdads, like several other Shiite clans that hail from Lebanon's eastern Bekaa Valley, maintain virtual private armies and have long had a troubled relationship with the Lebanese state, as well as with the country's two most powerful and organized Shiite militia and political parties, Hezbollah and the Amal movement.
On Wednesday, the Beirut-based al-Mayadeen television station broadcast what it said were armed members of the Meqdad family. One could be heard interrogating two captive Syrians identifying themselves as members of the Free Syrian Army, or FSA, the grouping of local militias and defected soldiers fighting President Assad's regime.
On Monday, an FSA unit said it had abducted Hassan Salim Meqdad, a Lebanese national in Syria, and accused him of being a member of Hezbollah. It claimed that Mr. Meqdad had entered Syria with almost 1,500 Hezbollah members to fight alongside the Assad regime.
Although Hezbollah has long backed the Assad regime, it issued a statement Tuesday denying this, adding that Mr. Meqdad wasn't a member of its organization.
People close to Hezbollah said the group was "exercising maximum restraint" to avoid being dragged into sectarian war in Lebanon and worse, a Shiite-on-Shiite fight. Hezbollah appeared to be controlling its constituents against showing force in the streets.
"This is an incident when you want Hezbollah to have an active role, but it's impossible for it to do so. The stakes are extremely high," said Amal Saad-Ghoreyb, a political analyst close to the group.
The Meqdad clan said it kidnapped a Turkish citizen in Beirut on Wednesday. Later in the day, Lebanon's New TV broadcast a short interview of a man it identified as a Turkish appliance-company worker being held by the clansmen, who said he had been kidnapped after he left the airport in Beirut earlier in the day.
Turkey's foreign ministry confirmed late Wednesday that a Turkish male citizen, Aydin Tufan Tekin, had been taken hostage in Lebanon and said Turkish diplomats were working to obtain his release.
Lebanese officials couldn't be immediately reached to comment.
In Syria's capital, Damascus, a fuel tanker truck exploded Wednesday near a hotel used as the headquarters and residence of the U.N. observer mission to Syria, wounding three people, Syrian officials and state media said.
The attack happened one day before consultations in New York on the fate of the mission, whose mandate expires by the end of the week.
Syrian state media said a "terrorist armed group"—the term the government has used for the rebels now waging an insurgency against it—had attached an explosive device to the fuel truck. Footage from the early-morning attack in Damascus broadcast by Syrian and Arab television stations showed a thick black plume of smoke billowing from the scene shortly after the blast.
No U.N. staff members were injured in the blast, said Juliette Touma, spokeswoman for the U.N. mission in Syria. Syria's Deputy Foreign Minister Faisal al-Mokdad met representatives of the U.N. mission staying at the hotel and said later that they were unscathed in the blast, and expressed his government's pride that not a single member of the U.N. mission has been harmed since the start of their mandate in late April.
—Farnaz Fassihi, Nada Raad and Leila Hatoum contributed to this article.
