Coalition warplanes have pounded a stronghold of the Islamic State group in Syria amid uncertainty over the fate of a US hostage the jihadists claim was killed in an earlier raid.
The United Arab Emirates, meanwhile, said it would station a squadron of F-16 warplanes in Jordan to support it in strikes against the IS who burned alive a captured Jordanian airman.
The parents of American Kayla Jean Mueller said they were “hopeful” she was still alive, after IS said she had been buried under rubble following a strike by a Jordanian warplane on their self-proclaimed capital Raqa.
The United States said there was no proof that the 26-year-old aid worker from Arizona had been killed.
Mueller’s parents appealed to her captors to contact them and for her safe return, in a statement carried by NBC News.
“This news leaves us concerned, yet, we are still hopeful that Kayla is alive. We have sent you a private message and ask that you respond to us privately,” said Carl and Marsha Mueller.
The Syrian Observatory for Human Rights said the US-led coalition fighting IS bombarded the Raqa area on Saturday for a second consecutive day.
More than 30 IS fighters had been killed in raids Friday around Raqa, said the Britain-based monitor.
A coalition statement said it had carried out a total of 11 air strikes against IS in Syria and 15 in Iraq during a 24-hour period up to Saturday morning, including in Raqa.
It said one air strike struck multiple IS weapons storage facilities in the Raqa area.
Jordanian state media said its warplanes had launched new anti-IS raids Saturday, for the third consecutive day.
Coalition partner UAE said an unspecified number of F-16s would be deployed in Jordan to support the Hashemite kingdom’s military in the fight against “the brutal terrorist organisation” IS.
An activist in Raqa who asked not to be identified said unconfirmed reports indicate Mueller had been moved recently from a women’s prison in the city to an IS camp farther east.
The camp “has recently been the target of intense coalition raids”, he said. “At the moment, we cannot confirm whether she was killed in the raids.”
Jordan – still reeling from the brutal murder of pilot Maaz al-Kassasbeh – rejected the jihadists’ claim that its warplanes killed Mueller, calling it an “old and sick trick” to deter coalition strikes.
US authorities have never given figures on the number of Americans kidnapped in Syria, sticking to a policy of complete silence.
Mueller travelled to the Syrian-Turkish border in 2012 to help refugees fleeing the civil war and was captured in Aleppo after leaving a Doctors Without Borders (MSF) hospital.
IS, a Sunni extremist group, has seized swathes of territory in Syria and Iraq and imposed an extreme interpretation of Islam on the areas under its control.