Just hours after a video surfaced showing the ISIS terrorist group executing a captive Jordanian pilot by burning him alive, Jordan is preparing to execute five terrorist prisoners in revenge, according to a report.

Speaking to Sky News Arabic under condition of anonymity, a Jordanian security official claimed Sajida al-Rishawi - a failed female suicide-bomber whose release ISIS had demanded in a previous video in exchange for Japanese hostage Kenji Goto - would have her execution sentence expedited along with four other Islamist terrorists, in response to the horrific execution of pilot Maaz al-Kassasbeh.

The five convicted terrorists would be executed "within hours" the source claimed.

Shortly after, another official told the AFP news agency that al-Rishawi would be "executed at dawn," but did not mention any other executions.

"The sentence of death pending on... Iraqi Sajida al-Rishawi will be carried out at dawn," the security official said on Tuesday, speaking on condition of anonymity.

In an official statement to Jordanian state TV, a Jordanian army spokesman confirmed al-Kassasbeh's death and vowed "revenge", without elaborating further.

"The military forces announce that the hero pilot, Muath al-Kaseasbeh, has fallen as a martyr, and ask God to accept him with the martyrs," Mamdouh al-Ameri said in a statement, translated by the Associated Press.

"While the military forces mourn the martyr, they emphasize his blood will not be shed in vain. Our punishment and revenge will be as huge as the loss of the Jordanians," he added.

US President Barack Obama also issued a response to the gruesome execution video Tuesday, saying that if it was authenticated it just shows the organization's "barbarity", and would strengthen the resolve of the international coalition mobilized against it.

"Should in fact this video be authentic, it's just one more indication of the viciousness (and) barbarity of this organization," Obama said, adding it would "redouble the vigilance and determination on the part of the global coalition to make sure" ISIS is "ultimately defeated."

And the general leading the US-led war against ISIS also denounced the "savage" execution of al-Kassasbeh.

"US Central Command strongly condemns ISIL's savage murder" of Lieutenant Maaz al-Kassasbeh and "will fight this barbaric enemy until it is defeated," General Lloyd Austin, head of the US Central Command, said in a statement.

Meanwhile, Jordanian state TV reported that al-Kassasbeh was in fact executed as early as January 3rd. 

And analysts, including Middle East expert Aymenn Tamimi, also pointed to a posts on Twitter a month ago by anti-ISIS activists, claiming already then that Kassasbeh had been "burned to death."

Tamimi told Arutz Sheva it was likely the Islamic State group only released the video now because "Jordan called IS' bluff by demanding proof the pilot was alive."

ISIS had previously offered to free Japanese hostage Kenji Goto in return for Sajida al-Rishawi, but the deal stalled after the jihadists inexplicably balked at Jordan's demand for proof that al-Kassasbeh was alive.

If reports he was in fact executed as far back as a month ago are true, it would mean he was already dead when the offer of a prisoner swap was made.