The U.S. military says the Jordanian warplane that crashed in Syria was not shot down by Islamic State (IS) militants.
The Jordanian F-16 fighter was lost on December 24 near the northeastern city of Raqqa, the extremist group's stronghold.
A pro-IS website published several photographs showing the pilot, identitied as 26-year-old Mu'ath Safi Yousef al-Kaseasbeh.
IS militants said they shot down the plane with a heat-seeking missile.
Jordan’s armed forces and the U.S. Central Command (CENTCOM) confirmed that the extremist group took captive the pilot.
But CENTCOM said "evidence clearly indicates" that the plane was not shot down.
It added that it would not tolerate the IS group's attempts to “misrepresent or exploit this unfortunate aircraft crash for their own purposes."
It did not say what could have caused the plane to crash.
The Jordanian army said Jordan holds the IS group and its supporters “responsible for the safety of the pilot and his life."
Meanwhile, Kasasbeh's father issued an appeal to IS leaders through a Jordanian newspaper.
"May Allah plant mercy in your hearts and may you release my son," he said.
UN Secretary-General Ban Ki-moon called on the Jordanian pilot to be treated "in accordance with international humanitarian laws."
This is the first U.S.-led coalition aircraft to be lost on Syrian territory since air strikes on IS targets there began in September.
The air forces of Jordan, the United States, United Arab Emirates, Saudi Arabia, and Bahrain have launched hundreds of strikes in the country over the past three months.
IS fighters have downed Iraqi and Syrian government planes in the past.
In neighboring Iraq, a suicide bomber blew himself up among a group of pro-government Sunni militiamen near the capital, Baghdad, killing at least 24 people.
The dead include Sunni militia fighters and Iraqi soldiers, while dozens of others were wounded in the December 24 blast.
The militia men had gathered at a military base in the town of Madain to receive their salaries.
The militias, known as Sahwa or the Awakening Councils, are comprised of Sunni fighters who had joined U.S. troops to battle Al-Qaeda during the height of Iraq's insurgency in 2007 and 2008.
Those Sunni militia fighters are now battling the extremist Sunni-led Islamic State (IS) militant group.
No one immediately claimed responsibility for the bombing, although similar attacks in the past have been claimed by the IS group.
With reporting by Reuters, AP and dpa