ISIS-affliliated group suspected of bombing Hamas security headquarters May 5, 2015Hamas terrorists in Gaza. (Emad Nassar/Flash90)(Emad Nassar/Flash90)ISIS-affliliated group suspected of bombing Hamas security headquartersISIS flag recently displayed on Temple Mount in Jerusalem, near Al Aqsa mosque. (Temple Institute)Hamas security headquarters in Gaza was bombed hours after the Supporters of the Islamic State in Palestine posted an ultimatum online.By: Lauren Calin, World Israel NewsA bomb exploded at Hamas security headquarters in Gaza City hours after the terrorist organization received a threat from a Salafist group calling itself the Supporters of the Islamic State in Palestine. Hamas has been conducting raids and mass arrests against Salafist groups, which it sees as a threat to its rule. Damage from the blast appears to be minor, and there were no reported injuries.Hamas has been conducting an extensive campaign against Salafist individuals and organizations in Gaza. For example, security forces arrested a Salafist leader last month, whom Hamas claims is an ISIS supporter. In an online statement, the Supporters of the Islamic State in Palestine said, “Hamas and its security forces have 72 hours from the release of this statement to free all Salafist [jihadist] prisoners…. Our soldiers are ready to act against chosen targets at the end of this ultimatum.”It is not yet known whether the bombing was connected to the statement. However, Hamas has received many similar threats in the past and views Salafist terrorists as a threat to its autocratic rule over Palestinians in the Gaza Strip. The Salafists, for their part, see the Hamas terror organization, which is ideologically aligned with the Muslim Brotherhood, as insufficiently extreme in its interpretation of Islam.Read Egypt proposes 2-day ceasefire plan to return 4 Israeli hostagesGaza has been rocked by a series of explosions in recent months. However, the primary target has been the property of Fatah officials. Hamas and the Fatah-dominated Palestinian Authority created a unity government last spring, but tensions have been running high, with mutual accusations of corruption and betrayal.A study of seven Arab countries by the Arab Center for Research and Policy Studies in Doha, Qatar, last November found that 24% of Palestinians describe their view of ISIS as positive or positive to some extent. However, a March poll by the Palestinian Center for Policy and Survey Research found that 86% of Palestinians consider ISIS to be a “radical group that does not represent true Islam.” FatahGazaHamasISISIslamic StatePalestinian Authority