Amman: The Islamic State group threatened to execute a captured Jordanian pilot "immediately" unless Amman frees an Iraqi female jihadist by sunset Thursday in exchange for a Japanese hostage.
In a new audio recording, a voice identifying itself as Japanese journalist Kenji Goto says his captors will kill airman Maaz al-Kassasbeh if the militant on death row is not handed over at the Turkish border in return for Goto`s life.
At the Turkish border post of Akcakale, which faces the IS-held Syrian town of Tel Abyad, dozens of journalists including some Japanese were waiting for a possible swap.
It is not clear from the unverified message, which was distributed by IS-linked Twitter accounts and reported by monitor SITE Intelligence Group, if Kassasbeh would be freed.
The Jordanian army said it was examining the new message.
"Our priority is Maaz," a military spokesman said.
Japan`s Chief Cabinet Secretary Yoshihide Suga told journalists the recording seemed genuine.
"We are in the process of confirming it, but it is highly probable that the voice is Mr. Goto`s," he said.
The apparent communication breaks a silence from the extremists since their previous 24-hour deadline to release Iraqi jihadist Sajida al-Rishawi expired at around 1400 GMT Wednesday.
The new deadline falls when the sun sets in the Iraqi city of Mosul at around 1500 GMT.
Amman has offered to free the Iraqi woman, who was convicted for her part in triple-hotel bombings in the Jordanian capital in 2005 that killed 60 people, if IS releases their airman."Jordan is ready to release the prisoner Sajida al-Rishawi if the Jordanian pilot is freed unharmed," state television quoted a government spokesman as saying Wednesday.
"From the start, the position of Jordan was to ensure the safety of our son, the pilot Maaz al-Kassasbeh," it added.
The government spokesman made no mention of Japanese hostage Goto.
After conflicting reports on Wednesday about the status of the possible swap, Jordan arrested two managers of a website for spreading rumours that Rishawi had already been released.
The owner of the Saraya News site, Hashim al-Khalidi, and editor-in-chief Seif Obeidat could face up to 15 years in prison if convicted.
The kingdom is under heavy pressure at home and from Japan -- a major aid donor -- to save Kassasbeh as well as Goto.
Kassasbeh was captured on December 24 after his F-16 jet crashed while on a mission against the jihadists over northern Syria.
This week the pilot`s father begged the government to save his son "at any price".
Japan, which plays no military part in the fight against jihadists, was thrust onto the front line last week when a video appeared in which Goto and Haruna Yukawa, a self-described contractor, were seen kneeling in the desert.
A masked knife-wielding militant said Tokyo had 72 hours to pay a $200 million ransom if it wanted to spare their lives.When that deadline expired, new pictures appeared to show Yukawa had been beheaded, and a voice identifying itself as Goto demanded the release of Rishawi.
In their next communication, on Tuesday, IS demanded Rishawi be handed over in exchange for Goto within 24 hours or both he and Kassasbeh would be killed.
Japan has appealed for Amman`s help, aware that Jordan holds the key to Goto`s safety, but also knowing that intense domestic pressure means the Jordanians must prioritise Kassasbeh.
Jordanians have taken to social media to offer messages of support for the pilot, with some writing that his life was "more important" than that of the "terrorist" Rishawi.
The Japanese public has rallied around Goto, a respected war reporter and humanitarian. Though they largely support Prime Minister Shinzo Abe`s handling of the crisis, that may change if the journalist does not come home alive.
Goto`s mother, Junko Ishido, was at Japan`s parliament Wednesday in a failed bid to meet Abe. After being refused an appointment, she issued a plea for her son`s life through assembled media.
"Prime Minister Shinzo Abe," Ishido said. "Please continue your utmost efforts in negotiating with the Jordanian government until the last minute. There is not much time left."