The "so-called" Daesh group posted a taped video message of the nine Lebanese soldiers, who were captured by the group at the beginning of this month.
The group said they the soldiers have only have three days to live if the Lebanese government did not act and help win their release.
The soldiers asked the government to release captured Daesh fighters so they can be freed.
The nine soldiers were captured when Daesh fighters based on the Syrian side of the borders with Lebanon attacked the Lebanese border town of Arsal and fought fierce battles with the Lebanese army and Hezbollah.