IS claims coalition airstrikes killed American hostage in Raqqa

The Islamic State (IS) on Friday claimed that bombings by the anti-IS coalition have killed an American hostage held by the group.

A message from IS published by the SITE Intelligence Group said that the female American aid worker was killed after a building she was being held in was destroyed by bombings in the IS ‘capital’ of Raqqa in northern Syria.

“The failed Jordanian aircraft killed an American female hostage,” said the message. “No mujahid was injured in the bombardment, and all praise is due to Allah.” Mujahid means fighter.

The reports are still unconfirmed – Fox News says the CIA are looking into them – and some have expressed scepticism over IS’s claim.

A photo released by IS purportedly showing the destroyed building is seemingly dated February 5, raising questions about its authenticity.

A US state department spokesperson told reporters Friday that they couldn't "confirm this report in any way".

The woman, thought to be Kayla Jean Mueller, is allegedly the only American hostage still being held by IS after disappearing in August 2013 after driving into Aleppo with her Syrian boyfriend.

Mueller's family meanwhile urged media to be restrained in their reporting of the IS claim about the aid worker.

"The family... request that media cautiously report on her background, work and current situation and limit speculation on her situation, and consider the implications for her security before publishing," said a statement by her parents, Marsha and Carl Mueller.

Mueller was taken captive after leaving a Medecins Sans Frontieres (Doctors Without Borders) hospital, according to the family statement, released via Arizona senator John McCain.

MSF noted that she had been visiting the facility with a friend contracted to do some repairs, and was detained as she headed to the bus station in Aleppo, from which she was meant to depart for Turkey.

National Security Council spokeswoman Bernadette Meehan would only say: "We are obviously deeply concerned by these reports. We have not at this time seen any evidence that corroborates ISIL's claim."

Mueller's parents, who live in Prescott, Arizona, said their daughter has devoted her career "to helping those in need in countries around the world" since graduating from Northern Arizona University in 2009.

She lived and worked with humanitarian aid groups in northern India, Israel and the Palestinian territories, before returning home to Arizona in 2011 and working at an HIV/AIDS clinic and a women's shelter.

The suffering of Syrian refugees prompted her to head to the Turkey-Syria border in December 2012 to work with the Danish Refugee Council and the humanitarian group Support to Life, their statement said.

Thousands gathered in Jordan's capital Amman on Friday, a day after Jordan's warplanes launched dozens of strikes against the Islamic State group in response to the burning alive of a pilot captured in Syria.

The demonstrations, who filled a road 5km strech of road in downtown Amman, held a mass prayer ceremony followed by chants in solidarity with King Abdullah II and the family of the pilot, Muaz Kasasbeh.

Jordan's military said "dozens of jet fighters" struck IS targets on Thursday morning, "hitting training camps of the terrorist groups as well as weapons and ammunition warehouses." It did not say where the targets were located.