Jordan executed two death-row jihadists at dawn on Wednesday after vowing an "earth-shattering" response to avenge the burning alive of one of its fighter pilots by the Islamic State group.
Would-be Iraqi female suicide bomber Sajida al-Rishawi and Iraqi Al-Qaeda member Ziad al-Karboli were hanged at 4:00 am local time (0200 GMT), government spokesman Mohammad al-Momani said.
A security source said the executions were carried out at Swaqa prison south of the capital Amman in the presence of an Islamic legal official.
Jordan had promised to begin executing Islamic extremists on death row at daybreak in response to the murder of Muath al- Al-Kassasbeh, who was captured by IS when his plane went down in Syria in December.
Rishawi, 44, was condemned to death for her participation in deadly attacks in Amman in 2005 and IS had offered to spare Al-Kassasbeh's life and free a Japanese hostage -- who was later beheaded -- if she were released.
Karboli was sentenced to death in 2007 on terrorism charges, including the killing of a Jordanian in Iraq.
Jordan had on Tuesday vowed to avenge the killing of Al-Kassasbeh, hours after a graphic video emerged online purporting to show the caged 26-year-old F-16 fighter pilot engulfed in flames.
The video -- the latest in a series of gruesome recorded killings of hostages by IS -- prompted global revulsion and vows of continued international efforts to combat the Sunni Muslim extremist group.
Jordan, a crucial ally of Washington in the Middle East, is one of five Arab countries that has joined a US-led coalition of countries carrying out air strikes against IS in Syria and Iraq.
Jordan's King Abdullah II, who was visiting Washington as the video came to light, recorded a televised address to his shocked and outraged nation.
The king, once in the military himself, described Al-Kassasbeh as a hero and vowed to take the battle to IS.
The army and government vowed to avenge the pilot's murder, with Momani saying: "Jordan's response will be earth-shattering.
"Whoever doubted the unity of the Jordanian people, we will prove them wrong," he said.
US President Barack Obama, who hosted Abdullah in a hastily organised Oval Office meeting, led international condemnation of the murder, decrying the "cowardice and depravity" of IS.
"The president and King Abdullah reaffirmed that the vile murder of this brave Jordanian will only serve to steel the international community's resolve to destroy ISIL," a National Security Council spokesman said after the pair met, using an alternative name for IS.
The Obama administration had earlier reaffirmed its intention to give Jordan $3 billion in security aid over the next three years.
Al-Kassasbeh was captured in December when his jet crashed over northern Syria on a mission that was part of the coalition air campaign against the jihadists.
Jordanian state television suggested he was killed on January 3, before IS offered to spare his life and free Japanese journalist Kenji Goto in return for Rishawi's release.
British Prime Minister David Cameron called the murder "sickening" while UN chief Ban Ki-moon labelled it an "appalling act".
Japan's Prime Minister Shinzo Abe condemned it as "unforgivable".
The highly choreographed 22-minute video shows Al-Kassasbeh at a table recounting coalition operations against IS, with flags from the various Western and Arab countries in the alliance projected in the background.
It then shows Al-Kassasbeh dressed in an orange jumpsuit and surrounded by armed and masked IS fighters in camouflage.
It cuts to him standing inside a cage and apparently soaked in petrol before a masked jihadist uses a torch to light a trail of flame that runs to the cage and burns him alive.
The video also offered rewards for the killing of other "crusader" pilots.
IS had previously beheaded two US journalists, an American aid worker and two British aid workers in similar highly choreographed videos.
Shiraz Maher, from the International Centre for the Study of Radicalisation at King's College London, described the footage as "simply the most horrific, disgusting thing I have seen from Islamic State in the last two years".
"They clearly want to make a real point. This is the first individual whom they have captured who has been directly involved with the Western coalition in fighting IS. It is different from the aid workers... This is an act of belligerence.
"Every time you think they cannot commit anything worse -- they open up another trapdoor."
The Islamic State group last year declared an Islamic "caliphate" as it rampaged across Iraq and Syria in a brutal offensive of executions and forced religious conversions.
Al-Kassasbeh's plane was the first loss of an aircraft since the US-led coalition launched strikes against IS last year.
US Central Command said that the group still had the ability "to conduct small-scale operations" despite months of air strikes.
But, it said, "their capacity to do so is degraded and their momentum is stalling."