An al-Qaida-linked militant group holding Lebanese soldiers and police released a video of the captive men today, as officials continue mediation to release the men.
The ongoing captivity of some 20 Lebanese security men by militants in Syria has emerged as one of the most serious spillovers of violence from the neighbouring conflict, now in its fourth year.
Militants from Syria seized the men when they overran the border town of Arsal, killing and kidnapping soldiers and police.
At least eight of the men are being held by the Syrian al-Qaida affiliate, the Nusra Front, which has a history of releasing detainees unharmed.
Others are being held by the extremist Islamic State group, which has decapitated two Lebanese soldiers in their captivity. The men's beheadings outraged Lebanon and sparked days of violence against Syrian refugees in the country.
The urgency of the Lebanese men's situation was underscored by the today release of a video showing the beheading of a British aid worker by Islamic State group fighters. David Haines was abducted in Syria last year.
The Islamic State has also beheaded two American journalists, James Foley and Steven Sotloff, and has killed many more Syrians and Iraqis.
In the two-part, 20-minute video released today by the Nusra Front, one Lebanese soldier enquired after his mother, and another burst into tears as he spoke to his family.
The video was spliced with montages of dead Syrian children and others suffering from hunger, as the words "Who will pay the price?" flashed across the screen.
Lebanon is negotiating for the men's release through mediation by officials from Qatar. The Nusra Front is demanding the release of accused Islamic militants from Lebanese detention, as well as money.
They are also demanding that the Lebanese Shiite group Hezbollah stop fighting in Syria alongside the forces of President Bashar Assad.
Today, Lebanese Prime Minister Tammam Salam travelled to the Qatari capital of Doha and held talks with senior officials there. Qatar is a major backer of Syrian rebel groups.
Qatar has also played a role in mediating the release of hostages held by Syrian rebels.
The tiny, energy-rich Gulf state earlier this year helped mediate the release of a group of Greek Orthodox nuns held by the Nusra Front in exchange for dozens of women held in Syrian government prisons.
