The gruesome death of 26-year-old Lt. Muath Al-Kaseasbeh, captured while participating in airstrikes by a U.S.-led coalition targeting the militants, sparked outrage across the Middle East and anti-Islamic State protests in Jordan.
King Abdullah II, a staunch Western ally, rushed back to Jordan, cutting short a Washington trip to try to persuade his people to support an even tougher line against the militants. Rallying such backing is pivotal for Jordan's continued role in the coalition.
Public opinion in Jordan has been ambiguous — growing demands for revenge against the militants have been mixed with misgivings about Jordan's role in a bombing campaign widely seen as serving Western interests.
The extremists, meanwhile, appeared to be goading Jordan. In Raqaa, the Islamic State group's de facto capital, the militants gleefully played al-Kaseasbeh's slaying on outdoor projectors, with some chanting "God is great," according to militant video posted online Wednesday that conformed to Associated Press reporting of the event.
In the 20-minute video, the pilot displayed signs of having been beaten, including a black eye. Toward the end of the clip, he is shown wearing an orange jumpsuit. He stands in an outdoor cage as a masked militant ignites a line of fuel leading to it.
The video of his purported killing was released on militant websites and bore the logo of the extremist group's al-Furqan media service. The clip featured the slick production and graphics used in previous Islamic State group videos. It could not immediately be confirmed independently by the AP.
A wave of condemnation washed across the Middle East on Wednesday, signaling that the Islamic State group militants might have overplayed their hand by putting their brutality toward a fellow Muslim on display. Some said this could trigger a backlash among Sunni Muslims in the region, the main reservoir of potential supporters.
At the same time, Jordan faces increasing internal and external threats from the militants. Jordan borders areas of Islamic State group's self-declared caliphate. There also have been signs of greater support for the group's militant ideas among Jordan's young and poor.
Following the pilot's death, Jordan launched what it said would be a tough campaign against the Islamic State group. In a first response, Jordan executed Sajida al-Rishawi and Ziad al-Karbouly, two Iraqis linked to al-Qaida, government spokesman Mohammed al-Momani said. Another official said they were executed by hanging. Authorities said the pair would be buried later in Jordan.
Al-Rishawi had been sentenced to death after her 2005 role in a triple hotel bombing that killed 60 people in Amman orchestrated by al-Qaida in Iraq, the predecessor of the Islamic State group. Al-Karbouly was sent to death row in 2008 for plotting terror attacks on Jordanians in Iraq.
Islamic State group militants purportedly had demanded Jordan release al-Rishawi in exchange for the pilot. Over the past week, Jordan had offered to trade her, but froze any swap after failing to receive any proof that the pilot was still alive.
The Jordanian military said, without elaborating, that the pilot was killed Jan. 3, suggesting officials knew any attempt to trade would be in vain.
Al-Kaseasbeh had fallen into the hands of the militants when his F-16 crashed near Raqqa. He was the first airman participating in the U.S.-led bombing raids against militant positions in Syria and Iraq to be captured.
The pilot's father, Safi Yousef al-Kaseasbeh, urged his government to "take revenge for Muath and to take revenge for the country, even before Muath."
Late Tuesday, dozens of people chanting against Islamic State marched toward the royal palace. Waving a Jordanian flag, they chanted, "Damn you, Daesh!" — using the Arabic acronym of the group — and "We will avenge, we will avenge our son's blood."
Al-Kaseasbeh was from a tribal area in southern Jordan's Karak district. The tribes are considered a mainstay of support for the monarchy, but the pilot's capture strained that relationship. During the weeks of uncertainty about the pilot, relatives criticized the government's handling of the crisis and Jordan's participation in the anti-Islamic State group alliance.
However, the tone has changed since the announcement of his death, with family members and other Jordanians speaking out against the militants.
"There is no religion accepts such act," Amman resident Hassan Abu Ali said. "Islam is a religion of tolerance. (The Islamic State group) have nothing to do with Islam. This is criminal act."
Across the Middle East, religious and political leaders offered angry denunciations and called for blood as some on television wept when talking about the pilot.
The head of Sunni Islam's most respected seat of learning, Egypt's Al-Azhar, described the militants as enemies of God and the Prophet Muhammad, saying they deserved the Quran-prescribed punishment of death, crucifixion or the chopping off of their arms.
"Islam prohibits the taking of an innocent life," Ahmed al-Tayeb, Al-Azhar's grand sheik, said in a statement, adding that by burning the pilot to death, the militants violated Islam's prohibition on the mutilation of bodies, even during wartime.
The Islamic State group has released a series of gruesome videos showing the beheading of captives, including two American journalists, an American aid worker and two British aid workers. Tuesday's was the first to show a captive being burned alive.
The latest video was released three days after another video showed the purported beheading of a Japanese journalist, Kenji Goto. A second Japanese hostage was apparently killed earlier last month.
U.S. Rep. Duncan Hunter Jr., a California Republican, said after a meeting with the king that Abdullah had been visibly angry and promised to retaliate against the militants.
"They're starting more sorties tomorrow than they've ever had. They're starting tomorrow," Hunter told the Washington Examiner in an interview published online Tuesday night.
Hunter added the king also said: "The only problem we're going to have is running out of fuel and bullets."
Associated Press writers Hamza Hendawi in Cairo, Diaa Hadid in Beirut and Mohammed Daraghmeh in Ramallah, West Bank, contributed to the report.
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