BEIRUT — Spillover from the Syrian conflict hit Lebanon in a frightening new way Wednesday with a mass abduction of more than 30 Syrians inside Lebanese territory, which their captors called revenge for the kidnapping of a relative inside Syria.
Members of a powerful Lebanese Shi’ite family who captured the Syrians, displayed in a video shown on Lebanese television, threatened to cause havoc in the streets and go on an extended kidnapping spree inside Lebanon until their family member, taken hostage by Syrian rebels, was set free.
‘‘The next few hours and next few days will determine what will happen,’’ one masked captor said outside a family property in a Shi’ite suburb of Beirut. Another member of the family that captured the Syrians, Hatem al-Mikdad, brother of the Lebanese hostage in Syria, said if he was not released soon, ‘‘we will kill all of them.’’
Anxiety quickly spread through Lebanon about possible instability, and extra security precautions were taken in Beirut. By Wednesday afternoon, according to Lebanese officials, additional guards had been assigned to the embassies of Qatar, Saudi Arabia, and Turkey, the main allies of the Syrian insurgency. Saudi Arabia and Qatar advised their citizens to leave Lebanon immediately.
While the circumstances of the kidnappings were in dispute, the events reflected Lebanon’s vulnerability to violence reverberating from Syria since the uprising against President Bashar Assad began nearly 18 months ago. Extended families with differing allegiances straddle both countries, and the use of hostages signaled the rise of abduction as a tactic by antagonists in the conflict.
Lebanon, with a divided government that is often unwilling to confront private militias, has already been shaken by violent clashes between supporters and opponents of the Syrian government, especially near the Lebanon-Syria border. Neither the police nor the army responded to the abductions Wednesday.
Fears of further abductions increased as Lebanese television networks reported that shelling and airstrikes by the Syrian military in Azaz, a suburb of Aleppo, Syria’s largest city, killed some or all of the 11 Lebanese pilgrims who had been kidnapped by rebels in May. Activists said many more people may have been killed in Azaz as well.
Those claims could not be independently verified.
The families of the 11 Lebanese pilgrims, angered by reports out of Azaz, also began kidnapping their own Syrians. They delivered three men to the Mikdad family compound here, parading them before Lebanese television cameras. All three, looking stunned, said they worked for a shipping company owned by a businessman from Aleppo: Two said they had helped the Syrian opposition by sending media reports from Lebanon.
The third accused Israel of creating unrest in Syria and said: ‘‘I have nothing to do with all of this.’’
In interviews with reporters, the relatives of the Lebanese man kidnapped on Monday, Hassane Salim al-Mikdad, said they had taken the hostages to avenge his abduction.
Some members of the Mikdad family, part of a powerful Shi’ite tribe in the Bekaa Valley near the Syrian border — where the captives appeared to have been caught and held — said that it did not intend to accelerate the Syrian war’s spread to other countries in the region. They described the abductions as personal and tribal.
‘‘We don’t want to get into a conflict,’’ one relative said in an interview with Al Mayadeen, the pan-Arab television network based in Beirut, as a dozen camouflaged men with automatic weapons could be seen surrounding the hostages, which the captors said were members of the Free Syrian Army, the main armed group fighting Assad’s forces. ‘‘We just want to get him released.’’
The kidnappings in Lebanon came as fighting inside Syria was punctuated by shellings and clashes in several cities. The day in Damascus began with a large blast.
Explosives hidden in a diesel tanker truck detonated behind a hotel used by the dwindling UN mission in Damascus, which is scheduled to leave in less than a week unless its mandate is extended. The hotel is situated near a Syrian military depot.
Juliette Touma, a spokeswoman for the UN mission, confirmed the explosion, near the Dama Rose hotel, where the mission members stay, but said none of them were hurt.
A rebel brigade in Damascus took responsibility for the bombing, saying it had targeted the military complex, not the hotel.
In Aleppo, reporters observed an L-39 fighter jet and MI-8 helicopters of the Syrian air force firing rockets at targets in a central neighborhood of the sprawling metropolis, a battleground between the armed forces and insurgents for the past three weeks.