I think Israel has bigger issues to worry about, like their northern border with Syria, which is now controlled by al-Nusra Front.

Via IBT:

An Islamic State-affiliated jihadi group in Gaza has declared war on Israel after claiming responsibility for two rocket attacks over the past two weeks.

A group calling itself the Sheikh Omar Hadeed Brigade in Quds claims that it fired a rocket on 26 May which landed near the Israeli city of Ashdod as well as another on June 3 that also hit the city. Israel responded with air strikes in Gaza on Thursday.

The first rocket was widely believed to have been fired by Islamic Jihad and the IS-affiliated Omar Brigade claim – which came in a statement on June 1 – cannot be independently verified. The group took responsibility for Wednesday night’s rocket in a second statement.

It has warned Israel that there will be more attacks: “Ashdod is the beginning. What’s coming is worse.”

Gaza is currently embroiled in an internal power struggle between Hamas and various salafi groups, of which the Omar Brigades appear to be most prominent.

On June 2, Hamas security forces killed an IS supporter in a shoot-out at his home in Gaza City and in May the Palestinian Islamist group – which has controlled the strip since 2006 – demolished a salafi mosque in central Gaza near Khan Younis.

While the Omar Brigades latest statement is explicit in its threat towards Israel, the bulk of the group’s anger is directed at Hamas, which it accuses of arresting and jailing salafis across the strip, as well as confiscating their weapons and torturing them.