Which Hamas leaders have been targeted in assassination attempts?

(FILES) An undated handout photo shows Mohammed Deif, the head of the Ezzedine al-Qassam Brigades, the military wing of the Palestinian militant group Hamas at an undisclosed location.

The head of Hamas' military wing, Mohammed Deif, was killed in an Israeli airstrike in Gaza last month, the Israeli military said on Thursday, its eighth attempt to kill him.