Jordan has launched new air strikes against the Islamic State of Iraq and the Levant (ISIL) in Syria, a day after King Abdullah II pledged to avenge the death of Jordanian military pilot Moaz al-Kassasbeh.

Jordan's army did not disclose what country was targeted during the operation on Thursday, but Al Jazeera has learned that Abdullah told Kassasbeh's father Safi al-Kassasbeh that the fighter jets flying over their town have just returned from Raqqa, the ISIL stronghold in Syria.

"Planes from the Jordanian Royal Forces have just arrived from Raqqa now after bombarding and pounding them," Kassasbeh said after he was given the information by the visiting king.

"God willing we will end their existence in Syria. We ask God to help us annihilate them."

Al Jazeera has also learned from sources in the Iraqi border police of Anbar province, in western Iraq, that Jordanian troops have moved closer towards the Iraqi border, near the Rowaished area opposite the Iraqi city of Trebil.

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The sources said the movement of a large number of troops was not unusual in the past, and that those forces have set up a camp there in the past.

Jordan is part of a US-led military coalition which has bombed ISIL targets in Syria and Iraq, but until now Jordanian jets are only known to have carried out raids in Syria.

ISIL controls a territory covering areas between Syria and Iraq.

The execution of Kassasbeh, who was captured by ISIL when his F-16 jet went down in Syria in December, has prompted anger in Jordan and boosted support for military action against the group.

"Jordan's resolve has been stiffened by this tragic murder," Al Jazeera's Nisreen El-Shamayleh, reporting from Karak, said.

"Those who didn't believe ISIL was a threat to the country now say the war against the group is theirs."

Abdullah cut short a visit to the US and flew back to Amman on Wednesday after the video emerged of Kassasbeh's killing.

On Wednesday, Jordan executed two Iraqis on death row - female would-be suicide bomber Sajida al-Rishawi and al-Qaeda operative Ziad al-Karbouli.

On Thursday, Queen Rania also joined Abdullah, paying her respects to the female members of the Kassasbeh family.