The Croatian government said it was "doing all it can" after a group claiming to be Islamic State militants released a video in which it threatened to behead a Croatian hostage.
Late Wednesday, Croatia’s government released a statement, read on state television, saying it was “doing all it can to promptly resolve the difficult situation,” although it did not elaborate on measures being taken.
Croatian Foreign Minister Vesna Pusic left for Cairo Thursday, a day after a video showed a man who identified himself as Tomislav Salopek said he would be executed within 48 hours if Egypt's government fails to release Muslim women held in prisons.
The Foreign Ministry said Pusic was in contact with Egyptian officials.
Salopek, 30 and a father of two, is shown in the video wearing a yellow jumpsuit and reading a note in English. He said he had been captured by Islamic State militants July 22.
The video shows Salopek kneeling in the desert before a knife-wielding masked man in military fatigues and next to a black Islamic flag often used by the extremists.
His reference to “Muslim women” apparently refers to Islamists who have been arrested in Egypt in a broad government crackdown on dissent.
Egypt, a majority Muslim country, now holds thousands of Islamists and suspected supporters of the outlawed Muslim Brotherhood group in prison following the 2013 military overthrow of Islamist President Mohammed Morsi.
Pusic, who is expected to meet with her Egyptian counterpart, also traveled with Salopek's wife, Natasa.
The video, which was circulated widely on social media by Islamic State sympathizers Wednesday, would be the first known posting featuring a Western hostage held by Sinai Province, which changed its name from Ansar Bayt al-Maqdis after it pledged allegiance to the Islamic State jihadist movement late last year.
'New' Suez Canal
The threat to execute Salopek came a day before Egypt’s inauguration of the "new" Suez Canal in the port city of Ismailiya. Hundreds of foreign dignitaries, including French President Francois Hollande, are expected to attend.
The Egyptian government had no immediate comment on the video Wednesday.
In recent months, Islamic militants in Sinai have launched increasingly sophisticated attacks that have killed dozens of Egyptian soldiers and police.
Salopek says he worked for CGG Ardiseis, a French oil-and-gas company that has an office in Cairo.
Croatia's Foreign Ministry confirmed that one of its nationals was kidnapped in Cairo last month.
The Islamic State group was behind several beheadings last year, including U.S. journalist James Foley, fellow American Steven Sotloff; British aid workers David Haines and Allan Henning; American aid worker Abdul-Rahman Kassig; and Japanese hostages Haruna Yukawa and Kenji Goto.
Some material for this report came from Reuters, AP and AFP.