Hamas Prime Minister Ismail Haniyeh has threatened to boycott unity talks with Fatah unless members of his group currently detained in the West Bank are released, Reuters reported Friday. During a sermon at a mosque in Rafah, Haniyeh said, "It is doubtful that this dialogue can succeed and it is doubtful that parties including Hamas would attend the coming round of dialogue in Cairo if we don't close the file on political arrests." "We are not naive and we won't accept that dialogue takes place while arrests continue," he was quoted as saying. The next round of reconciliation talks was set for August 25 in Cairo, where Egyptian mediators were hoping to encourage the two Palestinian factions to agree to a power-sharing arrangement ahead of elections set for January. On Saturday, Hamas announced it would put trial Fatah activists who managed to leave the Gaza Strip without obtaining permission, AFP quoted a statement made by the Gaza Justice Ministry. "Those who went to the conference in Bethlehem will be put to trial the moment they return to the Strip," the statement said. Earlier, some two dozen Fatah activists have sneaked out of the Gaza Strip, including a woman who said she hitched a ride with farmers on a donkey cart Friday to get past Hamas troops at a border checkpoint. The getaways were headed for Fatah's first convention in 20 years, set to start Tuesday in Bethlehem. More than 1,500 delegates are to attend, including 450 from Gaza. Travelers leaving Gaza have to present their documents at a Hamas checkpoint about 1.6 kilometers away from the Erez crossing into Israel. Several hundred meters closer to Erez, in an area off-limits to Hamas, another checkpoint is staffed by Palestinian Authority President Mahmoud Abbas loyalists, who coordinate with Israeli border officials. Since Hamas's violent takeover of the Strip in June 2007, few Gazans have been permitted to leave via Erez. They include medical patients with severe illnesses and business people. However, Israel has granted permits to nearly all the Fatah delegates from Gaza, in a gesture of support for Abbas. Israel has also permitted scores of Fatah delegates from the diaspora to enter the West Bank, according to PA negotiator Saeb Erekat. "It is really shameful that the big question mark is about delegates coming from Gaza," he said. Ghaliya Abu Sitte, 63, a Fatah delegate from the southern Gaza town of Khan Younis, said she left home early Friday, put on the traditional Muslim veil and long robe, took a taxi and got out a few hundred meters before the Hamas checkpoint. "I saw a donkey cart with two women who were collecting grass and wood, she said in an interview later Friday at a West Bank hotel. I got on the cart. I thought to myself, 'They won't notice me if I ride it.' I passed the Hamas checkpoint. They didn't stop me or ask me." Jadallah said others posed as medical patients on their way to treatment in Israel, including a female delegate who got in a wheelchair and was pushed by three fellow Fatah activists. Others bypassed the Hamas checkpoint by walking through orange groves. Abu Sitte said her daughter-in-law, who accompanied her for the trip to the border, was later detained by Hamas police. She and other Fatah delegates said they would return to Gaza after the conference and were not afraid of arrest. Hamas government spokesman Taher Nunu said Fatah activists had been warned against trying to sneak out. Anyone who defies these rules would face unpleasant procedures, he said.