Hamas named Gaza Strip chief Yahya Sinwar as its new political leader on Tuesday, after his predecessor, Ismail Haniyeh's, assassination in Tehran last week, which sent regional tensions soaring.
The group said earlier this week it was preparing to name a replacement of Haniyeh, who was widely seen as a moderate in the movement.
On Tuesday evening, Hamas named Sinwar as its new political leader, a controversial figure within Gaza and the movement who now occupies one of the leading positions in the movement.
"The Islamic Resistance Movement Hamas announces the selection of leader Yahya Sinwar as the head of the political bureau of the movement," a statement from the group said.
Minutes after the announcement, Hamas's armed wing, the Ezzedine Al-Qassam Brigades, said it fired a barrage of rockets from the Gaza Strip towards Israel.
The Israeli military and officials accuse Sinwar of being one of the masterminds of the October 7 attack on Israel, making him one of the country's most wanted militants.
His appointment as the new chief of Hamas comes less than a week after Haniyeh was killed, supposedly in an Israeli airstrike, in Tehran.
Israel has declined to comment on the killing but Iran has vowed revenge following the embarrassing security failure on its soil.
Israel has tried desperately to hunt down and assassinate Sinwar who is believed to be in Gaza but to not avail.
Hamas's 7 October attack resulted in the death of 1,198 people, mostly civilians, according to an AFP tally based on official Israeli figures.
During the attack, militants also seized 251 people, 111 of whom are still held captive in Gaza, including 39 the military says are dead.
Israel's devastating war on Gaza has so far killed at least 39,653 people, according to the health ministry in the Hamas-run territory, which does not provide details on civilian and militant deaths.