The militant Lebanese Shi-ite clan which is already holding 20 Syrians and a Turk says it will not take any more Sunni hostages.
It is pressing for the release of one of its clan members who is being held by rebels in Syria.
The anti-Assad Syrian National Council is also calling for the release of all the hostages.
Syrian National Council Chairman Abdulbaset Sieda said: “We call on the kidnappers and say to those who kidnapped the Lebanese: if you think that what you are doing serves the revolution you are wrong.”
There are fears that the kidnappings could herald the spread of the violence in Syria to Lebanon, a country whose politics have been influenced by Damascus for years.
Following warnings from their own countries, nationals from Saudi Arabia, Qatar and United Arab Emirates have begun leaving the country.
The confusion is such that reports say a French plane, which was diverted from Beirut for fear of violence, eventually landed in Damascus, where the passengers were asked to pay cash for the fuel needed to continue to Beirut.