The deal had stirred rare public anger against Hezbollah even among some of its closest allies, notably in Iraq, which is gearing for an offensive to reclaim Iraqi territory adjoining the area to which the fighters were relocating.

On Wednesday morning, the U.S.-led coalition moved to prevent the convoy from reaching its destination, the Islamic State-controlled town of Bukamal on the Syrian border with Iraq, according to U.S. military spokesman Col. Ryan Dillon.

The strikes took place in the vicinity of a desert town called Hamaymah, and though front lines are fluid and shifting in that part of Syria, it is the U.S. military’s understanding that the convoy is now stuck in Syrian government-held territory, Dillon said.

Hezbollah, Lebanese and Syrian fighters celebrate ISIS evacuation before U.S. airstrike

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“ISIS is a global threat, and to relocate terrorists from one place to another for someone else to deal with is not acceptable to the coalition,” he said, using an alternative acronym for the Islamic State. “Our goal is to prevent this convoy from moving to ISIS-held territory to reinforce ISIS elements there”

The airstrikes did not target the convoy itself, he added, because about 300 relatives are also traveling with the fighters. “There are families interspersed in this convoy, and we have taken that into account,” he said. “If we can separate them, we will strike them.”

A U.S. military statement subsequently said airstrikes targeted a number of individual vehicles and fighters “that were clearly identified as ISIS.”

Among those who criticized the deal was Iraqi Prime Minister Haider al-Abadi, who said at a news conference Tuesday night that it was “unacceptable” to negotiate with the Islamic State. Iraq is preparing for an offensive to recapture the Iraqi border town of Qaim, adjoining Bukamal, and the reinforcement of an extra 300 Islamic State fighters would make the task even more difficult, Iraqi security officials say.

Negotiated withdrawals are a common tactic in Syria and have frequently been used by President Bashar al-Assad’s government to reassert authority over communities that had fallen under rebel control in the six years of conflict. Many have involved fighters of an al-Qaeda affiliate, who have typically been relocated to the northern province of Idlib, bordering Turkey.

But this was the first publicly announced negotiated withdrawal involving the Islamic State on any battle front in Syria or Iraq since the war against the group began three years ago.

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Under the arrangement negotiated over the weekend, the fighters and their relatives were allowed to vacate a remote mountainous area spanning the Lebanese border for Bukamal. In return, Hezbollah secured the bodies of eight Lebanese soldiers who had been kidnapped by the Islamic State in 2014, the bodies of several Hezbollah fighters and the body of an Iranian military adviser who had been decapitated by the Islamic State during a battle on the Iraqi-Syrian border this month.

In a speech broadcast live across Lebanon on Monday night, Hezbollah leader Hassan Nasrallah claimed credit on Hezbollah’s behalf for negotiating the deal. He hailed it as a “great victory” that had decisively removed the last Islamic State fighters from Lebanese soil.

But in Iraq, where Hezbollah has many allies among the militias fighting the Islamic State, the backlash was swift and fierce. A photograph showing the militants traveling across Syria in an air-conditioned bus — marked with the words “Happy Journey” — was widely shared on social media, alongside biting criticisms of Hezbollah for failing to consider Iraq’s interests.

There was criticism in Lebanon, too, from the families of eight Lebanese army hostages hoping for their loved ones to be rescued and from Hezbollah’s political opponents, who expressed dismay that Hezbollah had negotiated with the extremists.

https://www.washingtonpost.com/world/middle_east/us-led-airstrikes-block-isis-fighters-escaping-under-a-hezbollah-negotiated-deal/2017/08/30/a9b40ea4-8d8c-11e7-9c53-6a169beb0953_story.html?utm_term=.c7ec6c418640&wpisrc=al_alert-world&wpmk=1