Hundreds of Palestinians demonstrated in the Gaza Strip late Sunday night, demanding a response to the IDF killing hours earlier of three Palestinian minors believed to have placed an explosive device near the southern border security fence.The demonstrators marched near the homes of Islamic Jihad members and senior Hamas leaders, Ismail Haniyeh.They demanded revenge and insisted that Islamic Jihad fulfill the promise they made over the weekend of "blood will be answered with blood.”According to the IDF, its aircraft struck “a squad of three terrorists who tried to sabotage [the Gaza security barrier] and apparently planted an explosive device” near it.Palestinian media reported that the dead were two 13-years olsd and one 14-year old from Khan Younis. Palestinians circulated photos of their dead bodies on social media.Hamas lashed out at both Israel and the Fatah-led Palestinian Authority in the West Bank for the deaths.Hamas spokesman Salah al-Bardawil said that “Zionist aircraft had assassinated three children,” but that as usual “the Zionist media announced that they were terrorists who planted explosive devices.” He added, “whether to believe them or to believe in the blood of the children who sought hope among the ruins of death, when their relatives [Fatah] continue to starve them and normalize their relationship with their murder.”There was an initial fear that Hamas or the Islamic Jihad would launch rockets against Israel overnight in response to the deaths.Just one day after, Islamic Jihad declared that a truce had been reached with Israel.The men had placed an explosive device by the barrier, the IDF said. Palestinian media reported that three people had been killed in the strike, with initial reports that they could have been minors.The violence broke 34 hours of calm, after a violent weekend in which Palestinians in Gaza fired 37 rockets at Israel and the IDF hit 95 military targets in the Hamas-ruled enclave.On Saturday, Islamic Jihad spokesman Daoud Shehab stated: "After contacts between the Islamic Jihad leadership and the brothers in Egypt it was agreed that a comprehensive cease-fire will begin immediately,” adding that ”the Islamic Jihad will abide by the cease-fire if the occupation (Israel) does the same.”In spite of that statement, Channel 2 reported that Hamas had told Israel it would halt the Gaza violence only in exchange for a monthly payment of $15 million in cash.On Sunday, Prime Minister Benjamin Netanyahu rejected that demand. “Yesterday we heard about an 'ultimatum' from Hamas to Israel. At no stage will Israel accept any ultimatum from Hamas. Israel will continue to act in accordance with Israeli interests and for Israel's security alone." But Israel has held off from launching a military offensive to halt the violence, nor has it halted the flow of goods and fuel into the Gaza Strip.The Security Cabinet which met Sunday did not issue any public statements.Together with the UN, Israel has worked to alleviate the electricity crisis there by helping to facilitate the shipment of Qatari-funded fuel into Gaza for its power plant. As a result of those efforts, the two million Palestinians in Gaza can receive eight hours of electricity a day instead of four.UN Special Coordinator for the Middle East Peace Process Nickolay Mladenov tweeted on Sunday, “As Gaza’s Power Plant runs 3rd turbine, people see electricity supply increase to 8 hrs. An opportunity that must not be wasted to de-escalate, resolve all humanitarian issues and reunite Palestinians under a single, democratic, national government.”Reuters and Maariv contributed to this report.