Kayla Mueller, the U.S. aid worker, kept as hostage for around 18 months by ISIS militants has been killed, as per her family sources. Based on an email with photograph received by her family over the weekend, the U.S. intelligence has come to the conclusion that she is no more. Islamic State on Friday provided an account of her death. It said that Mueller, 26, had been killed due to the bombing by the Jordanian fighter jets of the building in which she was kept hostage near Raqqa, a stronghold of the Islamic militant group in Syria. However, both the U.S. and Jordanian officials have expressed apprehensions about the circumstances of her death.

American Hostage Mueller is DeadMueller belonged to Prescott, Arizona, and have been considered to be the last American to have been held hostage by Islamic State which is an offshoot of al Qaeda controlling several parts of Iraq and Syria. However, as per Josh Earnest, a White House spokesperson, the U.S. government has the information about other Americans being held hostage in the region, but he did not elaborate or identify them. An American journalist, Austin Tice, suddenly disappeared in August 2012 in Damascus, and his family has again raised their voice on the matter last week. Nobody is aware of his whereabouts and the militant group holding him hostage, and his being alive. A British photojournalist, John Cantlie, is said to be another person held hostage by Islamic State. He was captured in November 2012 in the northern Syria. In the last few months, Islamic State has killed two Japanese, two Britons, and three Americans, all journalists or aid workers.

The family of Mueller issued a statement which said that they had been heartbroken to know her death, and made public a letter written by her in 2014 when she was held in captivity. Mueller, captured while coming out a hospital in Aleppo in northern Syria, worked previously in Turkey where she provided assistance to Syrian refugees. President Obama has expressed his deep anguish and determination to bring to book the culprits of Mueller, and offered condolences to her parents. On his orders last year, air strikes were launched on Islamic State strongholds in Syria and Iraq. The U.S. leads an international coalition against the Islamic terrorist group in these countries. The U.S. security officials doubted the veracity of the account of Mueller’s death, and believed that her death might have resulted in a combat situation under which the captors could not keep her safe. Mueller’s family even after the announcement of her death by Islamic State on Friday last, believed her to be alive.

Reacting on a report that Mueller’s family had been collecting donations to pay ransom to her captors; the U.S. officials reiterated that the government was against paying any ransom to terrorist groups as the money will be used to fund further terrorist activities. They reiterated government resolve to punish the culprits of Mueller’s death.