Eighty-two percent of Palestinians are of the opinion that the kidnapped Israeli soldier Gilad Shalit should only be released in exchange for Palestinian prisoners, a survey conducted by the Palestinian news agency Ma'an reported on Tuesday. The survey also showed that only six percent of Palestinians believed that Shalit should be released immediately. For the families of the thousands of Palestinian prisoners held in Israeli jails, the abduction on Sunday of IDF soldier Cpl. Gilad Shalit is good news because of the possibility that it could result in a prisoner swap with Israel. On Monday, many families and groups appealed to the Hamas kidnappers not to release the soldier unless Israel agreed to set free a large number of prisoners. In Ramallah and Gaza City, the relatives of some of the prisoners held press conferences during which they urged the kidnapers to resist efforts to release Shalit without security the release of their sons. The families also staged sit-in protests outside the offices of the International Committee for the Red Cross to demand the release of their sons. Palestinian analysts said a prisoner exchange would bolster Hamas's popularity. "If Hamas succeeds in releasing even a small number of prisoners, they will score many points," said one. "They will emerge as the heroes who managed to force Israel to release prisoners. This will undermine [Palestinian Authority Chairman] Mahmoud Abbas and his Fatah party." Abbas, who has been holding marathon talks in Gaza City with Hamas leaders over the past 48 hours, warned Prime Minister Ismail Haniyeh that Hamas would pay a "heavy price" unless it released the soldier unharmed, a source close to Abbas told The Jerusalem Post. "President Abbas has delivered a strong warning to Hamas. He has also instructed the Palestinian security forces to do their utmost to secure the release of the soldier. The president believes that the crisis could be resolved peacefully." A statement purportedly issued by the kidnappers on Monday said they would only release information on the fate of Shalit if Israel freed Palestinian women and teenagers under 18. "The occupation will not get any information about its missing soldier unless it abides by the following: release all female prisoners in Israeli jails and children under the age of 18," the statement said. But the families of the prisoners called on the kidnappers to seek the release of thousands of inmates. "This is a great opportunity to release thousands of prisoners," said Abu Adham, whose brother, Ali, has been in jail for nearly ten years. "We have been waiting for a prisoner exchange for many years. We have no doubt that Israel will be prepared to release thousands of Palestinians in exchange for the soldier. We don't want to see only a few hundred prisoners released." As news of the kidnapping spread on Sunday morning, many Palestinians expressed optimism that Israel would agree to the release of thousands of prisoners. SMS messages delivered through mobile phones carried greetings to the prisoners, many of whom are reported to be in "good mood" following the abduction of the soldier. Others have been distributing sweets to express their joy. In messages from a number of prisons, representatives of the inmates urged the kidnappers to keep the soldier alive with the hope that that would lead to a prisoner swap with Israel. Some of the prisoners were even interviewed by phone by a number of Arab TV stations and news agencies. Muayad Nasrallah, who is serving a 19-year term, said the top priority should be given to prisoners serving lengthy sentences. "We hope the issue of the kidnapped soldier will be used to secure the release of as many prisoners as possible, especially those who have been in jail for many years," he told the Bethlehem-based Maan News Agency. "We urge the kidnappers not to harm the soldier so that he could be exchanged for the prisoners." Abu Yusef, another prisoner who is serving an 11-year sentence, said most of his colleagues were "very happy" when they heard the news about the kidnapping of the soldier. "Many prisoners have packed their bags in anticipation of being released soon." Fatah legislator Issa Karake, who heads the Palestinian Prisoners' Club, a body that defends the rights of Palestinian prisoners held in Israel, called on the Israeli government to start "political and legal" preparation for a prisoner swap. "It's time that we pay attention to the plight of the Palestinian prisoners," he said. "This is the only opportunity to release over 10,000 prisoners. Israel has stubbornly refused to solve this issue through negotiations." Rami Allan, whose brother Muhammed is serving 12 years in an Israeli jail, said his parents "began singing out of joy" when they heard that an Israeli soldier had been kidnapped and was being held in the Gaza Strip. "They are very hopeful," he said. "But I'm personally not very optimistic because I think Israel is about to launch a massive military operation in the Gaza Strip." The Popular Front for the Liberation of Palestine on Monday called on the kidnappers to demand the release of the assassins of Tourism Minister Rehavam Ze'evi. The group said any prisoner swap should include its secretary-general, Ahmed Saadat, and four other PFLP members who were arrested by the IDF during a raid on a Jericho prison earlier this year. Abu Harun, a spokesman for one of the Fatah militias in the Gaza Strip, called on the kidnappers not to "let down" the prisoners and their families. He was speaking at a press conference in Gaza City, where he declared that his group was expecting Hamas to demand the release of all prisoners, including those belonging to Fatah.