Islamic State (IS) militants have captured the pilot of a Jordanian warplane that crashed in northern Syria, Jordan's military has confirmed.
The jihadist group claimed it had shot down the jet with a heat-seeking missile near the city of Raqqa.
It published photographs showing the pilot, who has been named as Flight Lieutenant Moaz Youssef al-Kasasbeh.
This is the first US-led coalition aircraft to be lost on IS territory since air strikes began in September.
Jordan is one of four Arab states which have bombed targets in Syria.
Plea for mercy
The confirmation that a Jordanian pilot had been captured came in a statement carried by the state news agency, Petra.
"During a mission Wednesday morning conducted by several Royal Jordanian Air Force planes against hideouts of the IS terrorist organisation in the Raqqa region, one of the planes went down and the pilot was taken hostage," a military source was quoted as saying.
"Jordan holds the group and its supporters responsible for the safety of the pilot and his life," the source added.
The source did not name the pilot, but Petra published a photo of Flt Lt Kasasbeh above its report.
Analysis: Jonathan Marcus, BBC defence correspondent
We do not know yet if the Jordanian aircraft suffered an engine failure or other technical problem, or if it was actually downed by IS air defences.
IS has been assumed to have a limited air defence capability - based not least on the sorts of shoulder-fired missiles that are rife in the region.
IS fighters have downed Iraqi and Syrian government aircraft and helicopters in the past. We also know that IS has overrun a number of Syrian air defence bases.
It is not clear if IS has personnel capable of operating any of these more sophisticated Soviet or Russian-supplied systems.
The US-led coalition permanently monitors the nature of the air defence threat and if the Jordanian aircraft was shot down then any potential lessons will be fed into the ongoing air campaign.
Earlier, the UK-based Syrian Observatory for Human Rights, said it had received reports from its network of activists that IS members had taken "an Arab pilot prisoner after shooting his plane down with an anti-aircraft missile near the city of Raqqa".
The pro-IS Raqqa Media Center also posted a photo on its Facebook page showing armed men taking the pilot out of what appeared to be a lake or river.
The man appeared able to stand but was bleeding from the mouth. He was wearing only a white T-shirt and was soaking wet.
A caption identified him as Lt Kasasbeh and later a photo appearing to show his military ID card was published.
Moaz Youssef al-Kasasbeh
- Born in the city of Karak in Jordan in 1988, he is 26 years old
- Has been a Royal Jordanian Air Force pilot for six years
- Currently holds the rank of flight lieutenant
- One of eight children, he got married in July
Lt Kasasbeh's father, Youssef al-Kasasbeh, confirmed his son had been captured in Syria in an interview with the Jordanian newspaper, Saraya.
Youssef al-Kasasbeh said he found out the news after the head of the RJAF informed another of his sons.
He appealed to IS leaders: "May Allah plant mercy in your hearts and may you release my son."
The air forces of Jordan, the US, UAE, Saudi Arabia, and Bahrain have carried out hundreds of air strikes on IS in Syria in the past three months.
Many of the targets have been in and around Raqqa, which is the de facto capital of the "caliphate" whose creation IS proclaimed in June.
Syrian government warplanes also regularly bomb Raqqa and the surrounding province. On Tuesday, an air strike killed more than 20 people, according to the Syrian Observatory.
Australia, Belgium, Canada, Denmark, France, the Netherlands and UK have joined the US in conducting air strikes on IS in neighbouring Iraq.
The BBC's Jim Muir in Beirut says the latest news will raise concern among the coalition nations about the level of armament available to the militants and the defensive measures deployed by coalition jets.
It may further diminish the appetite of Arab nations to take part in such operations, our correspondent adds.