The military confirmed the airstrikes, but did not provide details. Jordan TV, quoting military officials, reported that the strikes targeted Islamic State positions, but did not say in which country.
Jordan is part of a U.S.-led military coalition that has bombed IS targets in both countries since last fall, but until now Jordanian warplanes are only known to have carried out raids in Syria.
King Abdullah II pledged to step up the fight against the IS group after the militants burned a captive Jordanian pilot in a cage and released a video of the killing earlier this week. The images have sent waves of anger across the region.
On Thursday, warplanes roared overhead as the king paid a condolence visit to the family of the pilot, Lt. Muath al-Kaseasbeh, in his village in southern Jordan. The king pointed upward, toward the roar of the planes, as he sat next to the slain pilot's father, Safi al-Kaseasbeh.
Al-Kaseasbeh told the assembled mourners that the planes had returned from strikes over Raqqa, the de facto capital of the militants' self-declared caliphate. His son had been captured near Raqqa when his F-16 fighter plane went down in December.
Earlier this week, Islamic State displayed the video of the killing of the pilot on outdoor screens in Raqqa, to chants of "God is Great" from some in the audience, according to another video posted by the militants.
On Wednesday, Abdullah warned that Jordan's response "will be harsh because this terrorist organization is not only fighting us, but also fighting Islam and its pure values." He pledged to hit the militants "hard in the very center of their strongholds."
In Washington, leading members of Congress have called for increased U.S. military assistance to the kingdom. Currently, the United States is providing Jordan with $1 billion annually in economic and military assistance.
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