Islamic State supporters in Gaza have given the ruling Hamas movement a 48-hour deadline to halt its crackdown on them.

A statement sent to media on Monday did not say what the IS supporters would do if the crackdown continued. It included a claim of responsibility for a rocket fired at Israel from Gaza last week. The claim could not be independently verified.

Hamas has launched a crackdown on radical Islamists following a series of unclaimed bombings.

Hamas, an Islamic militant group that has ruled Gaza since 2007, sees more radical groups as a threat. The extremists accuse Hamas of being soft on Israel and failing to impose religious law.

It's unclear how many IS supporters are in Gaza, or if any have operational links to the extremist group.