Islamic State group supporters in Gaza have given ruling Hamas leaders a 48-hour deadline to stop a crackdown on them. The militants also claimed responsibility for a rocket fired at Israel from Gaza last week. The rocket landed near Gan Yavne in southern Israel, Israeli military officials said.

The threat to Hamas sent to Middle East reporters on Monday did not specify what would happen if the crackdown continued. Hamas has targeted Islamic State radicals in recent weeks after a series of unclaimed bombings. The crackdown resulted in the arrest of dozens of Salafi-jihadists who are affiliated with the Islamic State group, local media reported. Hamas also destroyed in May a mosque belonging to a group known as the “Supporters of the Islamic State in Jerusalem.” The Salafi group said Hamas had demolished the mosque “in a manner that even the Jewish and American occupation has not done,” the Egyptian daily newspaper Al-Masry al-Youm reported.

“In the light of Hamas’ new crackdown, we renew our loyalty to [ISIS Caliph Abu Bakr] al-Baghdadi and call on him to strengthen his influence and to launch a campaign in Palestine,” said a statement from Supporters of the Islamic State in Jerusalem released after the destruction of the mosque.

Meanwhile, Hamas security forces said Tuesday they had killed an Islamic State supporter in his home after a shoot-out in Gaza, Haaretz reported. Hamas spokesman Eyad Al-Bozum said the 27-year-old man died "during an attempt to arrest him," the Associated Press reported.

Islamic State supporters claim Hamas, the Sunni Muslim group that has governed the Gaza Strip since 2007, is too liberal and has failed to impose religious law. It's unclear how many ISIS supporters there are in Gaza, or if they have solid relations with the Islamic State group seizing territory in Syria and Iraq.