Egypt has offered to evacuate its citizens from Libya after Islamic State (IS) released photos which it says show 21 Coptic Egyptians kidnapped there.
President Abdul Fattah al-Sisi said Egyptians would be airlifted out of Libya, state-run news agency Mena said.
It came as a relative of one of those kidnapped told the BBC the victim's family had "collapsed emotionally".
A number of Egyptian Coptic Christians were kidnapped in two raids in Sirte, Libya, in December and January.
The pictures released by IS were published in the latest online edition of the group's magazine Dabiq.
A statement from the office of Egyptian President Abdul Fattah al-Sisi said a special committee was closely following events in order to "clarify the situation and learn the truth".
In Cairo, the families of the 21 hostages, who were working in Libya, have staged a protest accusing the president of not doing enough for them.
Speaking on Friday, an uncle of one of the kidnapped men said there was "an atmosphere of complete devastation" in his village following the publication of the pictures.
"We urge the president to exert his utmost efforts to bring our children back home," said Bashir Zaki. "We elected him and love him, he shouldn't neglect us."
Egypt's president Abdel Fattah al-Sisi reviews troops upon his arrival at Houari-Boumediene International Airport on June 25, 2014 in Algiers
Relatives of the kidnapped victims have called on Egyptian President Abdul Fattah al-Sisi to help
However, members of the Coptic community in Egypt have expressed scepticism about the offer to airlift people out of the country.
Youssef Sidhom, the editor of the Coptic newspaper in Cairo, told the BBC an airlift would require the assistance of local authorities, which he said would be difficult to achieve given that there was "no real state in Libya."
The foreign ministry has warned Egyptians not to travel to Libya, and said those already residing in the country should avoid areas of high tension.
The IS photographs show the captives with their hands cuffed behind their backs being marched in single file, lead by masked men dressed entirely in black.
The hostages are dressed in bright orange jumpsuits - the type worn by captives about to be executed by IS.
'Crusaders'
The militant group said the Egyptians had been recently kidnapped to avenge the fate of Muslim women "tortured and murdered by the Coptic church of Egypt".
The magazine says the group's expansion into Libya allows it "to easily capture Coptic crusaders".
It is not clear whether any or all of the hostages shown in the photographs are among those who were kidnapped in raids in Sirte on 31 December and 3 January.
Map showing the Libyan cities of Tripoli, Benghazi and Sirte and Egypt's capital Cairo - 3 December 2015
The coastal town is under the control of Islamic militant groups.
Thousands of Egyptians are currently working in Libya, many of them in the construction sector.
In February 2014, the bodies of seven Egyptian Christians who had been shot dead were found on a beach near the city of Benghazi.
Estimates as to the number of Copts living in Egypt today range from about nine million to 15 million out of a total population of about 87 million.